Submission #2741677

---

Source Code Expand

H, W = map(int, input().split())
C = [list(map(int, input().split())) for i in range(H)]

# 2次元累積和
S = [[0]*(W+1) for i in range(H+1)]

# ホワイトチョコの部分を負に
for h in range(H):
    for w in range(W):
        if (h+w) % 2 == 0:
            S[h+1][w+1] = C[h][w]
        else:
            S[h+1][w+1] = -C[h][w]

# 2次元累積和を計算
for h in range(2, H+1):
    S[h][1] += S[h-1][1]
for w in range(2, W+1):
    S[1][w] += S[1][w-1]
for h in range(2, H+1):
    for w in range(2, W+1):
        S[h][w] += S[h-1][w] + S[h][w-1] - S[h-1][w-1]

# 答えを計算
ans = 0
for i in range(1, H+1):  # 上
    for j in range(1, W+1):  # 左
        for k in range(i, H+1):  # 下
            for l in range(j, W+1):  # 右
                if S[k][l] - S[i-1][l] - S[k][j-1] + S[i-1][j-1] == 0:
                    ans = max(ans, (k-i+1)*(l-j+1))
print(ans)

Submission Info

Judge Result