33 lines
792 B
C++
33 lines
792 B
C++
#include <bits/stdc++.h>
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using namespace std;
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const int INF = 0x3f3f3f3f;
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const int N = 110;
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int g[N][N];
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int main() {
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int n;
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cin >> n;
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for (int i = 1; i <= n; i++)
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for (int j = 1; j <= n; j++) {
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cin >> g[i][j];
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// 累加出并记录同一列的前缀和
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g[i][j] += g[i - 1][j];
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}
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int res = -INF;
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// 枚举边界1，2
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for (int i = 1; i <= n; i++) // 起始行
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for (int j = i; j <= n; j++) { // 终止行
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// 枚举边界p
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int last = 0;
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for (int k = 1; k <= n; k++) {
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last = max(last, 0) + g[j][k] - g[i - 1][k];
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res = max(res, last);
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}
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}
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cout << res << endl;
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return 0;
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}
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