Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    for i in range(h):
        s = str(readline().rstrip().decode('utf-8'))
        for j in range(w):
            if s[j] == "#":
                a[i][j] = False
                ql.append([0, i, j])

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if a[xv][yv]:
                        ql.append([cost + 1, xv, yv])
                        a[i][j] = False
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        s = str(readline().rstrip().decode('utf-8'))
        for j in range(w):
            if s[j] == "#":
                a[i][j] = False
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv]:
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [["."] * w for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        s = str(readline().rstrip().decode('utf-8'))
        for j in range(w):
            if s[j] == "#":
                a[i][j] = "#"
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Runtime Error):
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [["."] * w for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        s = str(readline().rstrip().decode('utf-8'))
        for j in range(w):
            if s[j] == "#":
                a[i][j] = "#"
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Runtime Error):
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [["."] * w for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        s = str(readline().rstrip().decode('utf-8'))
        for j in range(w):
            if s[i][j] == "#":
                a[i][j] = "#"
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, xv, yv = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[xv + 1, yv], [xv - 1, yv], [xv, yv + 1], [xv, yv - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j, [[0, 1], [0, -1], [1, 0], [-1, 0]]])
                fq[i, j]

    while True:
        if len(ql) != 0:
            cost, xv, yv, nextv = ql.popleft()
            for nxv, nyv in nextv:
                if 0 <= xv + nxv < h and 0 <= yv + nyv < w:
                    if (xv + nxv, yv + nyv) not in fq:
                        fq[xv + nxv, yv + nyv]
                        if nxv == 1:
                            ql.append([cost + 1, xv + nxv, yv + nyv, [[0, 1], [0, -1], [1, 0]]])
                        elif nxv == -1:
                            ql.append([cost + 1, xv + nxv, yv + nyv, [[0, 1], [0, -1], [-1, 0]]])
                        elif nyv == 1:
                            ql.append([cost + 1, xv + nxv, yv + nyv, [[-1, 0], [1, 0], [0, 1]]])
                        elif nyv == -1:
                            ql.append([cost + 1, xv + nxv, yv + nyv, [[-1, 0], [1, 0], [0, -1]]])
        else:
            break
    print(cost)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    while True:
        if len(ql) != 0:
            cost, xv, yv = ql.popleft()
            for xv, yv in [[xv + 1, yv], [xv - 1, yv], [xv, yv + 1], [xv, yv - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq:
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(cost)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, xv, yv = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[xv + 1, yv], [xv - 1, yv], [xv, yv + 1], [xv, yv - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq and a[xv][yv] == ".":
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    sys.setrecursionlimit(2000)
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]

    mt = 0
    while True:
        if len(ql) != 0:
            cost, xv, yv = ql.popleft()
            mt = max(mt, cost)
            for xv, yv in [[xv + 1, yv], [xv - 1, yv], [xv, yv + 1], [xv, yv - 1]]:
                if 0 <= xv < h and 0 <= yv < w:
                    if (xv, yv) not in fq:
                        ql.append([cost + 1, xv, yv])
                        fq[xv, yv]
        else:
            break
    print(mt)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
import sys
import collections


def solve():
    input = sys.stdin.readline
    mod = 10 ** 9 + 7
    h, w = list(map(int, input().rstrip('\n').split()))
    a = [list(str(input().rstrip('\n'))) for _ in range(h)]
    ql = []
    ql = collections.deque(ql)
    fq = collections.defaultdict(list)
    for i in range(h):
        for j in range(w):
            if a[i][j] == "#":
                ql.append([0, i, j])
                fq[i, j]
    m_cost = 0
    while True:
        if len(ql) != 0:
            cost, x, y = ql.popleft()
            m_cost = max(m_cost, cost)
            for x, y in [[x + 1, y], [x - 1, y], [x, y + 1], [x, y - 1]]:
                if 0 <= x < h and 0 <= y < w:
                    if (x, y) not in fq and a[x][y] == ".":
                        ql.append([cost+1, x, y])
                        fq[x, y]
        else:
            break
    print(m_cost)


if __name__ == '__main__':
    solve()


Fixed submission:
import sys
import collections


def solve():
    readline = sys.stdin.buffer.readline
    h, w = list(map(int, readline().split()))
    a = [[True] * w for _ in range(h)]
    ql = collections.deque()
    for i in range(h):
        s = list(str(readline().rstrip().decode('utf-8')))
        for j in range(w):
            if s[j] == "#":
                ql.append([0, i, j])
                a[i][j] = False
    while ql:
        cost, x, y = ql.popleft()
        for xv, yv in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
            if 0 <= xv < h and 0 <= yv < w:
                if a[xv][yv]:
                    ql.append([cost + 1, xv, yv])
                    a[xv][yv] = False
    print(cost)


if __name__ == '__main__':
    solve()