HDU4283(区间DP)

#include <cstdio>
#include <cstring>
#include <cmath>
#include <iostream>
#include <algorithm>
using namespace std;
#define maxn 111
#define maxm 8111111
#define INF 11111111111

long long dp[maxn][maxn], f[maxn][maxn];
int n;
long long a[maxn];
long long sum[maxn];

int main () {
    //freopen ("in", "r", stdin);
    int t, kase = 0;
    scanf ("%d", &t);
    while (t--) {
        scanf ("%d", &n);
        sum[0] = 0;
        for (int i = 1; i <= n; i++)
            scanf ("%lld", &a[i]);
        for (int i = 1; i <= n; i++)
            sum[i] = sum[i-1]+a[i];
        memset (f, 0, sizeof f);
        for (int i = n; i >= 1; i--) {
            for (int j = i; j <= n; j++) {
                f[i][j] = f[i+1][j]+a[i]*(j-i);
            }
        }
        for (int i = 0; i <= n+1; i++) {
            for (int j = 0; j <= n+1; j++) {
                dp[i][j] = INF;
            }
        }
        for (int i = 1; i <= n; i++)
            dp[i][i] = 0;
        for (int l = 1; l <= n; l++) {
            for (int i = 1; i+l <= n; i++) {
                for (int j = i; j+1 <= i+l; j++) {
                    int cnt1 = j-i+1, cnt2 = i+l-j;
                    int sum1 = sum[j]-sum[i-1], sum2 = sum[i+l]-sum[j];
                    dp[i][i+l] = min (dp[i][i+l], min (dp[i][j]+dp[j+1][i+l]+sum2*cnt1, dp[j+1][i+l]+f[i][j]+sum1*cnt2));
                }
            }
        }
        printf ("Case #%d: %lld\n", ++kase, dp[1]
);
    }
    return 0;
}