uva10304-最优排序二叉树

#include<stdio.h>
#include<string.h>
#define MAX_LEN 255
#define inf 1<<31-1
#define max(a,b) (((a) > (b)) ? (a) : (b))
#define min(a,b) (((a) < (b)) ? (a) : (b))
int dp[MAX_LEN][MAX_LEN];
int value[MAX_LEN];
int sum[MAX_LEN];
int main()
{
    int n;
    while(scanf("%d", &n) == 1) {
        memset(sum, 0, sizeof(sum));
        memset(dp, 0, sizeof(dp));
        for(int i=0; i<n; i++) {
            scanf("%d", &value[i]);
            if(i == 0) sum[i] = value[i];
            else sum[i] = sum[i-1] + value[i];
        }
        for(int d=0; d<n; d++)
            for(int l=0; l<n; l++) {
                int minv = inf;
                int r = (l + d) < n ? (l + d) : (n - 1);
                for(int k=l; k<=r; k++) {
                    int u;
                    int k1 = max(k - 1, l);
                    int k2 = min(k + 1, r);
                    u = dp[l][k1] + dp[k2][r];
                    u += sum[r] - sum[l]  + value[l] - value[k];
                    if(u < minv) minv = u;
                }
                dp[l][r] = minv;
            }
        printf("%d\n", dp[0][n-1]);
    }
    return 0;
}