Euler #85

def rectangles(length, width):
    combos = 0
    for x in range(1, length+1):
        for y in range(1, width+1):
            combos += (length+1-x)*(width+1-y)
    return combos

closest, bestarea = 10**10, 0
for a in range(1, 2*10**3):
    print(a)
    for b in range(1, 10**10):
        if rectangles(a, b) > 2*10**6:
            upperdiff = rectangles(a, b) - 2*10**6
            lowerdiff = 2*10**6 - rectangles(a, (b-1))
            if (upperdiff < lowerdiff) and (upperdiff < closest):
                closest = upperdiff
                bestarea = a*b
            if (lowerdiff < upperdiff) and (lowerdiff < closest):
                closest = lowerdiff
                bestarea = a*(b-1)
            break
print(bestarea)