LargestPlusSign.py

def orderOfLargestPlusSign(self, n, mines):
    N = n
    banned = {tuple(mine) for mine in mines}
    dp = [[0] * N for _ in range(N - 1, -1, -1)]
    ans = 0

    for r in range(N - 1, -1, -1):
        count = 0
        for c in range(N - 1, -1, -1):
            count = 0 if (r, c) in banned else count + 1
            dp[r][c] = count

        count = 0
        for c in range(0, N):
            count = 0 if (r, c) in banned else count + 1
            if count < dp[r][c]: dp[r][c] = count

    for c in range(N - 1, -1, -1):
        count = 0
        for r in range(N - 1, -1, -1):
            count = 0 if (r, c) in banned else count + 1
            if count < dp[r][c]: dp[r][c] = count

        count = 0
        for r in range(N):
            count = 0 if (r, c) in banned else count + 1
            if count < dp[r][c]: dp[r][c] = count
            if dp[r][c] > ans: ans = dp[r][c]

    return ans