Completed day 5, task 2

Day-5/day5-2.py

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+#!/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.")
+