Solution.py

class Solution:
    def isRectangleCover(self, rectangles: List[List[int]]) -> bool:
        area = 0
        minX, minY = rectangles[0][0], rectangles[0][1]
        maxX, maxY = rectangles[0][2], rectangles[0][3]
        cnt = defaultdict(int)

        for r in rectangles:
            area += (r[2] - r[0]) * (r[3] - r[1])

            minX = min(minX, r[0])
            minY = min(minY, r[1])
            maxX = max(maxX, r[2])
            maxY = max(maxY, r[3])

            cnt[(r[0], r[1])] += 1
            cnt[(r[0], r[3])] += 1
            cnt[(r[2], r[3])] += 1
            cnt[(r[2], r[1])] += 1

        if (
            area != (maxX - minX) * (maxY - minY)
            or cnt[(minX, minY)] != 1
            or cnt[(minX, maxY)] != 1
            or cnt[(maxX, maxY)] != 1
            or cnt[(maxX, minY)] != 1
        ):
            return False

        del cnt[(minX, minY)], cnt[(minX, maxY)], cnt[(maxX, maxY)], cnt[(maxX, minY)]

        return all(c == 2 or c == 4 for c in cnt.values())