HDU 2571 命运——DP

注意把边界赋值为-INF；

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>

using namespace std;

const int INF = 0x3f3f3f3f;
const int maxn = 1010;

int n, m, a[25][maxn], dp[25][maxn];

int main()
{
    int T; scanf("%d", &T);
    while (T--) {
        scanf("%d %d", &n, &m);
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                scanf("%d", &a[i][j]);
            }
        }
        for (int i = 1; i <= n; i++) {
            dp[i][0] = -INF;
        }
        for (int i = 1; i <= m; i++) {
            dp[0][i] = -INF;
        }
        dp[1][0] = dp[0][1] = 0;
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= m; j++) {
                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
                for (int k = 2; k <= j; k++) {
                    if (j % k == 0) {
                        dp[i][j] = max(dp[i][j], dp[i][j / k]);
                    }
                }
                dp[i][j] += a[i][j];
            }
        }
        printf("%d\n", dp[n][m]);
    }
    return 0;
}