From 9289b7558157d411d678cce9eb1756c61eabc4c1 Mon Sep 17 00:00:00 2001
From: Jake Charman <jake@jakecharman.co.uk>
Date: Wed, 30 Nov 2022 21:05:44 +0000
Subject: [PATCH] Directory Structure for 2022

---
 2021/Day-1/day1-1.py   | 28 ++++++++++++++
 2021/Day-1/day1-2.py   | 33 ++++++++++++++++
 2021/Day-10/day10-1.py | 34 +++++++++++++++++
 2021/Day-10/day10-2.py | 43 +++++++++++++++++++++
 2021/Day-2/day2-1.py   | 24 ++++++++++++
 2021/Day-2/day2-2.py   | 26 +++++++++++++
 2021/Day-3/day3-1.py   | 33 ++++++++++++++++
 2021/Day-3/day3-2.py   | 67 ++++++++++++++++++++++++++++++++
 2021/Day-4/day4-1.py   | 78 ++++++++++++++++++++++++++++++++++++++
 2021/Day-4/day4-2.py   | 86 ++++++++++++++++++++++++++++++++++++++++++
 2021/Day-5/day5-1.py   | 68 +++++++++++++++++++++++++++++++++
 2021/Day-5/day5-2.py   | 79 ++++++++++++++++++++++++++++++++++++++
 2021/Day-6/day6-1.py   | 21 +++++++++++
 2021/Day-6/day6-2.py   | 38 +++++++++++++++++++
 2021/Day-7/day7-1.py   | 20 ++++++++++
 2021/Day-7/day7-2.py   | 21 +++++++++++
 2021/Day-8/day8-1.py   | 12 ++++++
 2021/Day-8/day8-2.py   | 64 +++++++++++++++++++++++++++++++
 2021/Day-9/day9-1.py   | 31 +++++++++++++++
 19 files changed, 806 insertions(+)
 create mode 100644 2021/Day-1/day1-1.py
 create mode 100644 2021/Day-1/day1-2.py
 create mode 100644 2021/Day-10/day10-1.py
 create mode 100644 2021/Day-10/day10-2.py
 create mode 100644 2021/Day-2/day2-1.py
 create mode 100644 2021/Day-2/day2-2.py
 create mode 100644 2021/Day-3/day3-1.py
 create mode 100644 2021/Day-3/day3-2.py
 create mode 100644 2021/Day-4/day4-1.py
 create mode 100644 2021/Day-4/day4-2.py
 create mode 100644 2021/Day-5/day5-1.py
 create mode 100644 2021/Day-5/day5-2.py
 create mode 100644 2021/Day-6/day6-1.py
 create mode 100644 2021/Day-6/day6-2.py
 create mode 100644 2021/Day-7/day7-1.py
 create mode 100644 2021/Day-7/day7-2.py
 create mode 100644 2021/Day-8/day8-1.py
 create mode 100644 2021/Day-8/day8-2.py
 create mode 100644 2021/Day-9/day9-1.py

diff --git a/2021/Day-1/day1-1.py b/2021/Day-1/day1-1.py
new file mode 100644
index 0000000..7ac6a64
--- /dev/null
+++ b/2021/Day-1/day1-1.py
@@ -0,0 +1,28 @@
+#!/usr/bin/python3
+
+# Variables to hold our totals.
+increased = 0
+decreased = 0
+
+# Read in the input file and make it an array.
+with open('input.txt', 'r') as inputFile:
+    values = []
+    for line in inputFile:
+        values.append(int(line))
+
+# Loop through the array skipping the first value.
+for v in range(0, len(values)):
+    if(v == 0):
+        continue
+    
+    # Check each value against the one before it.
+    if(values[v - 1] < values[v]):
+        increased+=1
+    elif(values[v - 1] > values[v]):
+        decreased+=1
+    else:
+        pass
+
+# Print the output.
+print("Decreased: " + str(decreased))
+print("Increased: " + str(increased))
\ No newline at end of file
diff --git a/2021/Day-1/day1-2.py b/2021/Day-1/day1-2.py
new file mode 100644
index 0000000..0309acd
--- /dev/null
+++ b/2021/Day-1/day1-2.py
@@ -0,0 +1,33 @@
+#!/usr/bin/python3
+
+# Variables to hold our totals.
+increased = 0
+decreased = 0
+
+# Read in the input file and make it an array.
+with open('input.txt', 'r') as inputFile:
+    rawValues = []
+    for line in inputFile:
+        rawValues.append(int(line))
+
+# Sum up numbers in 3's and add them to a new array.
+values = []
+for i in range(0, len(rawValues) - 2):
+    values.append(rawValues[i] + rawValues[i+1] + rawValues[i+2])
+
+# Loop through the array skipping the first value.
+for v in range(0, len(values)):
+    if(v == 0):
+        continue
+    
+    # Check each value against the one before it.
+    if(values[v - 1] < values[v]):
+        increased+=1
+    elif(values[v - 1] > values[v]):
+        decreased+=1
+    else:
+        pass
+
+# Print the output.
+print("Decreased: " + str(decreased))
+print("Increased: " + str(increased))
\ No newline at end of file
diff --git a/2021/Day-10/day10-1.py b/2021/Day-10/day10-1.py
new file mode 100644
index 0000000..ae62c21
--- /dev/null
+++ b/2021/Day-10/day10-1.py
@@ -0,0 +1,34 @@
+#!/usr/bin/python3
+
+totalScore = 0
+
+closers = {
+    '(':')',
+    '{':'}',
+    '[':']',
+    '<':'>'
+}
+
+points = {
+    ')':3,
+    ']':57,
+    '}':1197,
+    '>':25137
+}
+
+with open('/home/jake/Documents/AoC-2021/Day-10/input.txt') as inputFile:
+    for line in inputFile:
+        line = line.strip('\n')
+        i = 0
+        expecting = []
+        i = 0
+        for char in line:
+            if(char in closers):
+                expecting.insert(0,closers[char])
+            else:
+                if(expecting[i] != char):
+                    totalScore += points[char]
+                    break
+                else:
+                    del expecting[i]
+print("Our total score was: " + str(totalScore))
\ No newline at end of file
diff --git a/2021/Day-10/day10-2.py b/2021/Day-10/day10-2.py
new file mode 100644
index 0000000..cd97d31
--- /dev/null
+++ b/2021/Day-10/day10-2.py
@@ -0,0 +1,43 @@
+#!/usr/bin/python3
+
+from statistics import median
+
+lineScores = []
+
+closers = {
+    '(':')',
+    '{':'}',
+    '[':']',
+    '<':'>'
+}
+
+points = {
+    ')':1,
+    ']':2,
+    '}':3,
+    '>':4
+}
+
+with open('/home/jake/Documents/AoC-2021/Day-10/input.txt') as inputFile:
+    for line in inputFile:
+        line = line.strip('\n')
+        expecting = []
+        invalid = False
+        for char in line:
+            if(char in closers):
+                expecting.insert(0,closers[char])
+            else:
+                if(expecting[0] != char):
+                    invalid = True
+                    break
+                else:
+                    del expecting[0]
+        if(invalid):
+            continue
+        else:
+            totalScore = 0
+            for e in expecting:
+                totalScore*=5
+                totalScore+=points[e]
+            lineScores.append(totalScore)
+print("The middle score is: " + str(median(lineScores)))
\ No newline at end of file
diff --git a/2021/Day-2/day2-1.py b/2021/Day-2/day2-1.py
new file mode 100644
index 0000000..c11806b
--- /dev/null
+++ b/2021/Day-2/day2-1.py
@@ -0,0 +1,24 @@
+#!/usr/bin/python3
+
+# Variables to hold our position.
+x = 0
+z = 0
+
+# Read in the input file. Split each line on the space.
+with open('input.txt', 'r') as inputFile:
+    values = []
+    for line in inputFile:
+        splitLine = line.split()
+
+        # Check the first word of each line to decide what to do.
+        if splitLine[0] == "forward":
+            x = x + int(splitLine[1])
+        elif splitLine [0] == "down":
+            z = z + int(splitLine[1])
+        elif splitLine [0] == "up":
+            z = z - int(splitLine[1])
+
+# Print our final values.
+print("X: " + str(x))
+print("Z: " + str(z))
+print("X * Z = " + str(x*z))
\ No newline at end of file
diff --git a/2021/Day-2/day2-2.py b/2021/Day-2/day2-2.py
new file mode 100644
index 0000000..f3688b1
--- /dev/null
+++ b/2021/Day-2/day2-2.py
@@ -0,0 +1,26 @@
+#!/usr/bin/python3
+
+# Variables to hold our position.
+x = 0
+z = 0
+aim = 0
+
+# Read in the input file. Split each line on the space.
+with open('input.txt', 'r') as inputFile:
+    values = []
+    for line in inputFile:
+        splitLine = line.split()
+
+        # Check the first word of each line to decide what to do.
+        if splitLine[0] == "forward":
+            x = x + int(splitLine[1])
+            z = z + (aim * int(splitLine[1]))
+        elif splitLine [0] == "down":
+            aim = aim + int(splitLine[1])
+        elif splitLine [0] == "up":
+            aim = aim - int(splitLine[1])
+
+# Print our final values.
+print("X: " + str(x))
+print("Z: " + str(z))
+print("X * Z = " + str(x*z))
\ No newline at end of file
diff --git a/2021/Day-3/day3-1.py b/2021/Day-3/day3-1.py
new file mode 100644
index 0000000..0a357c9
--- /dev/null
+++ b/2021/Day-3/day3-1.py
@@ -0,0 +1,33 @@
+#!/usr/bin/python3
+
+# Variables to hold our totals.
+gamma = ''
+epsilon = ''
+
+# Read in the input file. Split the file up into an array.
+values = []
+with open('input.txt', 'r') as inputFile:
+    for line in inputFile:
+        values.append(line.strip('\n'))
+
+# Add up all the 1 values for each bit, then use the length of the array to calculate the most common bit.
+for i in range(0, len(values[0])):
+    currentBitCount = 0
+    for value in values:
+        currentBitCount = currentBitCount + int(value[i])
+    
+    if((len(values) - currentBitCount) < currentBitCount):
+        gamma = gamma + '1'
+        epsilon = epsilon + '0'
+    elif((len(values) - currentBitCount) > currentBitCount):
+        gamma = gamma + '0'
+        epsilon = epsilon + '1'
+
+# Convert the binary strings to decimal ints.
+gammaInt = int(gamma, 2)
+epsilonInt = int(epsilon, 2)
+
+# Print results.
+print("Gamma is " + str(gamma) + " (" + str(gammaInt) + ")") 
+print("Epsilon is " + str(epsilon) + " (" + str(epsilonInt) + ")") 
+print("Gamma multiplied by Epsilon is: " + str(gammaInt * epsilonInt))
\ No newline at end of file
diff --git a/2021/Day-3/day3-2.py b/2021/Day-3/day3-2.py
new file mode 100644
index 0000000..9cf76b6
--- /dev/null
+++ b/2021/Day-3/day3-2.py
@@ -0,0 +1,67 @@
+#!/usr/bin/python3
+
+# Variables to hold our totals.
+keptNumbers = []
+co2 = 0
+o2 = 0
+
+# Read in the input file. Split the file up into an array.
+rawValues = []
+with open('input.txt', 'r') as inputFile:
+    for line in inputFile:
+        rawValues.append(line.strip('\n'))
+
+# Loop through twice, collecting the opposite set of results each time.
+for i in range(0,2):
+    values = rawValues
+    mostPopular=0
+
+    # Determine the most popular bit.
+    for bit in range(0, len(values[0])):
+        currentBitCount = 0
+        for value in values:
+            currentBitCount = currentBitCount + int(value[bit])
+        
+        # Keep values which contain the most popular bit.
+        if((len(values) - currentBitCount) < currentBitCount):
+            mostPopular = 1
+            for value in values:
+                if(value[bit] == str(mostPopular) and i == 1):
+                    keptNumbers.append(value)
+                elif(value[bit] != str(mostPopular) and i == 0):
+                    keptNumbers.append(value)
+
+        elif((len(values) - currentBitCount) > currentBitCount):
+            mostPopular = 0
+            for value in values:
+                if(value[bit] == str(mostPopular) and i == 1):
+                    keptNumbers.append(value)
+                elif(value[bit] != str(mostPopular) and i == 0):
+                    keptNumbers.append(value)
+
+        elif((len(values) - currentBitCount) == currentBitCount):
+            for value in values:
+                if(value[bit] == str(i)):
+                    keptNumbers.append(value)
+
+        values = keptNumbers
+        keptNumbers = []
+
+        # Break if we only have one value left.
+        if(len(values) == 1):
+            break
+
+    # Put the value in the right variable.
+    if(i == 0):
+        co2 = values[0]
+    elif(i == 1):
+        o2 = values[0]
+
+# Convert the binary numbers to ints.
+o2Int = int(o2, 2)
+co2Int = int(co2, 2)
+
+# Print results.
+print("O2 Generator reading is " + str(o2) + " (" + str(o2Int) + ")")
+print("CO2 Scrubber reading is " + str(co2) + " (" + str(co2Int) + ")")
+print("The readings multipied together is " + str(o2Int * co2Int))
\ No newline at end of file
diff --git a/2021/Day-4/day4-1.py b/2021/Day-4/day4-1.py
new file mode 100644
index 0000000..3710507
--- /dev/null
+++ b/2021/Day-4/day4-1.py
@@ -0,0 +1,78 @@
+#!/usr/bin/python3
+
+numbersDrawn = []
+boards = []
+
+# Function to check a given board for completed columns
+def checkColumns(board):
+    match = False
+    for i in range(0,len(board[0])):
+        for line in board:
+            if(line[i] == '*'):
+                match = True
+                continue
+            else:
+                match = False
+                break
+        if(match):
+            return True
+        else:
+            continue
+    return False
+
+# Function to check a given board for completed rows.
+def checkRows(board):
+    for line in board:
+        match = False
+        for num in line:
+            if(num == '*'):
+                match = True
+                continue
+            else:
+                match = False
+                break
+        if(match):
+            return True
+        else:
+            continue
+    return False
+
+# Open the file. Put the numbers to be drawn in one array and the boards in another.
+with open('/home/jake/Documents/AoC-2021/Day-4/input.txt', 'r') as inputFile:
+    numbersDrawn = inputFile.readline().split(',')
+    boardsFromFile = inputFile.readlines()[1:]
+    
+    currentBoard = []
+    for line in boardsFromFile:
+        currentLine = []
+
+        if(line == '\n'):
+            boards.append(currentBoard)
+            currentBoard = []
+            continue
+        
+        currentLine = line.split()
+        currentBoard.append(currentLine)
+    boards.append(currentBoard)
+
+# Mark off the numbers drawn on the boards.
+for i in range(0, len(numbersDrawn)):
+    for board in boards:
+        for line in board:
+            for num in range(len(line)):
+                if(line[num] == numbersDrawn[i]):
+                    line[num] = '*'
+
+        # Check for a winning board
+        if(checkRows(board) or checkColumns(board)):
+            print("Found winning board: " + str(board))
+            total = 0
+            for line in board:
+                for num in line:
+                    if(num != '*'):
+                        total = total+int(num)
+            score = total * int(numbersDrawn[i])
+            print("Total score of winning board is: " + str(score))
+            exit()
+        else:
+            continue
\ No newline at end of file
diff --git a/2021/Day-4/day4-2.py b/2021/Day-4/day4-2.py
new file mode 100644
index 0000000..7aa4083
--- /dev/null
+++ b/2021/Day-4/day4-2.py
@@ -0,0 +1,86 @@
+#!/usr/bin/python3
+
+numbersDrawn = []
+boards = []
+winningBoards = []
+
+# Function to check a given board for completed columns
+def checkColumns(board):
+    match = False
+    for i in range(0,len(board[0])):
+        for line in board:
+            if(line[i] == '*'):
+                match = True
+                continue
+            else:
+                match = False
+                break
+        if(match):
+            return True
+        else:
+            continue
+    return False
+
+# Function to check a given board for completed rows.
+def checkRows(board):
+    for line in board:
+        match = False
+        for num in line:
+            if(num == '*'):
+                match = True
+                continue
+            else:
+                match = False
+                break
+        if(match):
+            return True
+        else:
+            continue
+    return False
+
+# Open the file. Put the numbers to be drawn in one array and the boards in another.
+with open('/home/jake/Documents/AoC-2021/Day-4/input.txt', 'r') as inputFile:
+    numbersDrawn = inputFile.readline().split(',')
+    boardsFromFile = inputFile.readlines()[1:]
+    
+    currentBoard = []
+    for line in boardsFromFile:
+        currentLine = []
+
+        if(line == '\n'):
+            boards.append(currentBoard)
+            currentBoard = []
+            continue
+        
+        currentLine = line.split()
+        currentBoard.append(currentLine)
+    boards.append(currentBoard)
+
+# Mark off the numbers drawn on the boards.
+for i in range(0, len(numbersDrawn)):
+    for board in boards:
+        for line in board:
+            for num in range(len(line)):
+                if(line[num] == numbersDrawn[i]):
+                    line[num] = '*'
+
+        # Check for a winning board
+        if(checkRows(board) or checkColumns(board)):
+            if(board in winningBoards):
+                continue
+            else:
+                winningBoards.append(board)
+            if(len(winningBoards) < len(boards)):
+                continue
+            else:
+                print("Found final winning board: " + str(board))
+                total = 0
+                for line in board:
+                    for num in line:
+                        if(num != '*'):
+                            total = total+int(num)
+                score = total * int(numbersDrawn[i])
+                print("Total score of final winning board is: " + str(score))
+                exit()
+        else:
+            continue
\ No newline at end of file
diff --git a/2021/Day-5/day5-1.py b/2021/Day-5/day5-1.py
new file mode 100644
index 0000000..7ea0489
--- /dev/null
+++ b/2021/Day-5/day5-1.py
@@ -0,0 +1,68 @@
+#!/usr/bin/python3
+
+diagram = []
+totalPoints = 0
+
+# Read all the line segments into an array.
+segments = []
+with open('/home/jake/Documents/AoC-2021/Day-5/input.txt') as inputFile:
+    for line in inputFile:
+        segment = line.strip('\n').split(' -> ')
+        segments.append(segment)
+
+# Work out the bounds of our diagram and create an array for it.
+largestX = 0
+largestY = 0
+for segment in segments:
+    if(int(segment[0].split(',')[0]) > largestX):
+        largestX = int(segment[0].split(',')[0])
+    
+    if(int(segment[1].split(',')[0]) > largestX):
+        largestX = int(segment[1].split(',')[0])
+
+    if(int(segment[0].split(',')[1]) > largestY):
+        largestY = int(segment[0].split(',')[1])
+    
+    if(int(segment[1].split(',')[1]) > largestX):
+        largestY = int(segment[1].split(',')[1])
+
+
+for i in range(0, largestY+1):
+    diagLine = []
+    for i in range(0,largestX+1):
+        diagLine.append(0)
+    diagram.append(diagLine)
+
+# Run through the line segments and plot them on the diagram if they are horizontal or vertical.
+for segment in segments:
+    startingX = int(segment[0].split(',')[0])
+    startingY = int(segment[0].split(',')[1])
+    endingX = int(segment[1].split(',')[0])
+    endingY = int(segment[1].split(',')[1])
+    if((startingX == endingX) or (startingY == endingY)):
+        endX = endingX +1
+        startX = startingX
+        endY = endingY +1
+        startY = startingY
+
+        # Flip the start and end if the end is lower so our for loop will still run.
+        if(startingX > endingX):
+            endX = startingX +1
+            startX = endingX
+        if(startingY > endingY):
+            endY = startingY +1
+            startY = endingY
+        
+        for x in range(startX, endX):
+            for y in range(startY, endY):
+                diagram[y][x]+=1
+                 
+# Find points where two or more line segments overlap.                
+for line in diagram:
+    for num in line:
+        if(num > 1):
+            totalPoints+=1
+
+# Print the results
+print("There are " + str(totalPoints) + " points where two or more lines overlap.")
+
diff --git a/2021/Day-5/day5-2.py b/2021/Day-5/day5-2.py
new file mode 100644
index 0000000..a77d508
--- /dev/null
+++ b/2021/Day-5/day5-2.py
@@ -0,0 +1,79 @@
+#!/usr/bin/python3
+
+diagram = []
+totalPoints = 0
+
+# Read all the line segments into an array.
+segments = []
+with open('/home/jake/Documents/AoC-2021/Day-5/input.txt') as inputFile:
+    for line in inputFile:
+        segment = line.strip('\n').split(' -> ')
+        segments.append(segment)
+
+# Work out the bounds of our diagram and create an array for it.
+largestX = 0
+largestY = 0
+for segment in segments:
+    if(int(segment[0].split(',')[0]) > largestX):
+        largestX = int(segment[0].split(',')[0])
+    
+    if(int(segment[1].split(',')[0]) > largestX):
+        largestX = int(segment[1].split(',')[0])
+
+    if(int(segment[0].split(',')[1]) > largestY):
+        largestY = int(segment[0].split(',')[1])
+    
+    if(int(segment[1].split(',')[1]) > largestX):
+        largestY = int(segment[1].split(',')[1])
+
+for i in range(0, largestY+1):
+    diagLine = []
+    for i in range(0,largestX+1):
+        diagLine.append(0)
+    diagram.append(diagLine)
+
+# Run through the line segments and plot them on the diagram.
+for segment in segments:
+    startingX = int(segment[0].split(',')[0])
+    startingY = int(segment[0].split(',')[1])
+    endingX = int(segment[1].split(',')[0])
+    endingY = int(segment[1].split(',')[1])
+
+    # Create lists for the X and Y points our lines will go through.
+    if(startingX > endingX):
+        xStep = -1
+        endingX-=1
+    else:
+        xStep = 1
+        endingX+=1
+    if(startingY > endingY):
+        yStep = -1
+        endingY-=1
+    else:
+        yStep=1
+        endingY+=1
+
+    xList = list(range(startingX, endingX, xStep))
+    yList = list(range(startingY, endingY, yStep))
+
+    # If the line is horizontal or vertical there will be differing numbers of indexes so we need to loop though them separately.
+    if(len(xList) != len(yList)):
+        for x in xList:
+            for y in yList:
+                diagram[y][x]+=1
+    # Otherwise they will be identical and we need to increment both lists together.
+    else:
+        for i in range(0, len(xList)):
+            currentX = xList[i]
+            currentY = yList[i]
+            diagram[currentY][currentX]+=1
+
+# Find points where two or more line segments overlap.                
+for line in diagram:
+    for num in line:
+        if(num > 1):
+            totalPoints+=1
+
+# Print the results.
+print("There are " + str(totalPoints) + " points where two or more lines overlap.")
+
diff --git a/2021/Day-6/day6-1.py b/2021/Day-6/day6-1.py
new file mode 100644
index 0000000..7e69f13
--- /dev/null
+++ b/2021/Day-6/day6-1.py
@@ -0,0 +1,21 @@
+#!/usr/bin/python3
+
+# Open the file and read the one line into an array.
+fish = []
+with open('/home/jake/Documents/AoC-2021/Day-6/input.txt') as inputFile:
+    fish = inputFile.readline().strip('\n').split(',')
+    fish = [ int(x) for x in fish ]
+
+# Loop over the array decrementing and adding fish as required for 80 days.
+days = 0
+while days < 80:
+    for i in range(0, len(fish)):
+        if(fish[i] == 0):
+            fish[i] = 6
+            fish.append(8)
+        else:
+            fish[i] = fish[i] -1
+    days+=1
+
+# Print the results.
+print("Total fish afer " + str(days) + " days: " + str(len(fish)))
\ No newline at end of file
diff --git a/2021/Day-6/day6-2.py b/2021/Day-6/day6-2.py
new file mode 100644
index 0000000..85c5f59
--- /dev/null
+++ b/2021/Day-6/day6-2.py
@@ -0,0 +1,38 @@
+#!/usr/bin/python3
+
+# Open the file and read the one line into an array.
+fish = []
+with open('/home/jake/Documents/AoC-2021/Day-6/input.txt') as inputFile:
+    fish = inputFile.readline().strip('\n').split(',')
+    fish = [ int(x) for x in fish ]
+
+fishFrequency = []
+for i in range(0, 9):
+    fishFrequency.append(0)
+
+for f in fish:
+    fishFrequency[f]+=1
+
+# Loop over the array decrementing and adding fish as required for 80 days.
+days = 0
+origFish = []
+for num in fishFrequency:
+    origFish.append(num)
+while days < 256:
+    for i in range(1,len(fishFrequency)):
+            fishFrequency[i-1] = origFish[i]
+    fishFrequency[6] += origFish[0]
+    fishFrequency[8] = origFish[0]
+
+    origFish=[]
+    for num in fishFrequency:
+        origFish.append(num)
+
+    days+=1
+
+totalFish = 0
+for total in fishFrequency:
+    totalFish += total
+
+# Print the results.
+print("Total fish afer " + str(days) + " days: " + str(totalFish))
\ No newline at end of file
diff --git a/2021/Day-7/day7-1.py b/2021/Day-7/day7-1.py
new file mode 100644
index 0000000..001b1b2
--- /dev/null
+++ b/2021/Day-7/day7-1.py
@@ -0,0 +1,20 @@
+#!/usr/bin/python3
+
+# Read in the file and split it into an array.
+crabPositions = []
+with open('/home/jake/Documents/AoC-2021/Day-7/input.txt') as inputFile:
+    crabPositions = inputFile.readline().strip('\n').split(',')
+    crabPositions = [ int(x) for x in crabPositions]
+
+possiblePositions = list(range(min(crabPositions), max(crabPositions)))
+fuelForPositions = []
+
+# Calculate the lowest possible fuel usage.
+for i in possiblePositions:
+    fuelUsed = 0
+    for crab in crabPositions:
+        fuelUsed += abs(crab - i)
+    fuelForPositions.append(fuelUsed)
+
+# Print the results.
+print("Lowest possible fuel usage is " + str(min(fuelForPositions)) + " by moving to position " + str(possiblePositions[fuelForPositions.index(min(fuelForPositions))]))
\ No newline at end of file
diff --git a/2021/Day-7/day7-2.py b/2021/Day-7/day7-2.py
new file mode 100644
index 0000000..c688c1c
--- /dev/null
+++ b/2021/Day-7/day7-2.py
@@ -0,0 +1,21 @@
+#!/usr/bin/python3
+
+# Read in the file and split it into an array.
+crabPositions = []
+with open('/home/jake/Documents/AoC-2021/Day-7/input.txt') as inputFile:
+    crabPositions = inputFile.readline().strip('\n').split(',')
+    crabPositions = [ int(x) for x in crabPositions ]
+
+possiblePositions = list(range(min(crabPositions), max(crabPositions)))
+fuelForPositions = []
+
+# Calculate the lowest possible fuel usage.
+for i in possiblePositions:
+    fuelUsed = 0
+    for crab in crabPositions:
+        postitionsToMove = abs(crab - i)
+        fuelUsed += postitionsToMove/2*(1+postitionsToMove)
+    fuelForPositions.append(int(fuelUsed))
+
+# Print the results.
+print("Lowest possible fuel usage is " + str(min(fuelForPositions)) + " by moving to position " + str(possiblePositions[fuelForPositions.index(min(fuelForPositions))]))
\ No newline at end of file
diff --git a/2021/Day-8/day8-1.py b/2021/Day-8/day8-1.py
new file mode 100644
index 0000000..2b5621f
--- /dev/null
+++ b/2021/Day-8/day8-1.py
@@ -0,0 +1,12 @@
+#!/usr/bin/python3
+
+totalUnique = 0
+
+# Read in the input file.
+with open('/home/jake/Documents/AoC-2021/Day-8/input.txt') as inputFile:
+    for line in inputFile:
+        for output in line.strip('\n').split('|')[1].split():
+            if(len(output) in [2,3,4,7]):
+                totalUnique += 1
+
+print(totalUnique)
\ No newline at end of file
diff --git a/2021/Day-8/day8-2.py b/2021/Day-8/day8-2.py
new file mode 100644
index 0000000..7965767
--- /dev/null
+++ b/2021/Day-8/day8-2.py
@@ -0,0 +1,64 @@
+#!/usr/bin/python3
+
+finalTotal = 0
+
+# Function to find and return common chars in a string.
+def findCommon(s1, s2):
+    common = ""
+    for i in s1:
+        if(i in s2):
+            common += i
+    return common
+
+# Read in the input file. Put the signals and outputs in two 
+with open('/home/jake/Documents/AoC-2021/Day-8/input.txt') as inputFile:
+    for line in inputFile:
+        newNums = ['0','0','0','0','0','0','0','0','0','0']
+        out = ""
+        signals = line.strip('\n').split('|')[0].split()
+        output = line.strip('\n').split('|')[1].split()
+
+        for signal in signals:
+            if(len(signal) == 2):
+                newNums[1] = "".join(sorted(signal)) 
+            elif(len(signal) == 3):
+                newNums[7] = "".join(sorted(signal)) 
+            elif(len(signal) == 4):
+                newNums[4] = "".join(sorted(signal)) 
+            elif(len(signal) == 7):
+                newNums[8] = "".join(sorted(signal)) 
+            else:
+                continue
+
+        for signal in signals:
+            sortedSignal = "".join(sorted(signal))
+            if(sortedSignal in newNums):
+                continue
+            
+            if(len(signal) == 5):
+                # Check for 2.
+                if(len(findCommon(signal, newNums[4])) == 2 and len(findCommon(signal, newNums[1])) == 1 and len(findCommon(signal, newNums[7])) == 2):
+                    newNums[2] = "".join(sorted(signal))
+                # Check for 3.
+                elif(len(findCommon(signal, newNums[7])) == 3 and len(findCommon(signal, newNums[1])) == 2):
+                    newNums[3] = "".join(sorted(signal))
+                # Check for 5.
+                elif(len(findCommon(signal, newNums[4])) == 3 and len(findCommon(signal, newNums[1])) == 1):
+                    newNums[5] = "".join(sorted(signal))
+            elif(len(signal) == 6):
+                # Check for 6.
+                if(len(findCommon(signal, newNums[1])) == 1 and len(findCommon(signal, newNums[8])) == 6 and len(findCommon(signal, newNums[4])) == 3):
+                    newNums[6] = "".join(sorted(signal))
+                # Check for 9.
+                elif(len(findCommon(signal, newNums[7])) == 3 and len(findCommon(signal, newNums[4])) == 4):
+                    newNums[9] = "".join(sorted(signal))
+                # Check for 0.
+                elif(len(findCommon(signal, newNums[4])) == 3 and len(findCommon(signal, newNums[8])) == 6 and len(findCommon(signal, newNums[1])) == 2):
+                    newNums[0] = "".join(sorted(signal))
+        
+        for num in output:
+            sortedNum = "".join(sorted(num))
+            displayedNum = newNums.index(sortedNum)
+            out = str(out) + str(displayedNum)
+        finalTotal += int(out)
+        print(finalTotal)
\ No newline at end of file
diff --git a/2021/Day-9/day9-1.py b/2021/Day-9/day9-1.py
new file mode 100644
index 0000000..8110f36
--- /dev/null
+++ b/2021/Day-9/day9-1.py
@@ -0,0 +1,31 @@
+#!/usr/bin/python3
+
+sumOfLowest = 0
+map = []
+
+def checkSurrounding(list, x, y):
+    possibleX = [x, x-1, x+1]
+    possibleY = [y, y-1, y+1]
+
+    for newY in possibleY:
+        if(newY < 0 or newY >= len(list)):
+            continue
+        for newX in possibleX:
+            if(newX < 0 or newX >= len(list[0])):
+                continue
+            if(list[y][x] > list[newY][newX]):
+                return False
+    return True
+        
+with open('/home/jake/Documents/AoC-2021/Day-9/input.txt') as inputFile:
+    for line in inputFile:
+        lineList = list(line.strip('\n'))
+        lineList = [int(x) for x in lineList]
+        map.append(lineList)
+
+for x in range(len(map[0])):
+    for y in range(len(map)):
+        if(checkSurrounding(map, x, y)):
+            sumOfLowest += (map[y][x] + 1) 
+
+print("Sum of risk levels is: " + str(sumOfLowest))
\ No newline at end of file