四边形不等式优化学习地址：http://blog.csdn.net/u014800748/article/details/45750737 重点是：m(i,j)=min{m(i,k-1),m(k,j)}+w(i,j)(s(i,j-1)≤k≤s(i+1,j))（min也可以改为max） 知识点一样的题目：玲珑杯1066 参考链接： http://blog.csdn.net/acmore_xiong/article/details/53745970 http://blog.csdn.net/acmore_xiong/article/details/53744680 http://yangff.logdown.com/posts/138211 http://blog.csdn.net/u014800748/article/details/45750737
#include <bits/stdc++.h> using namespace std; int n, m, a[1005]; int p[1005][1005], sum[1005]; long long dp[1005][1005]; int main() { scanf("%d", &n); for(int i = 1; i <= n; i++) scanf("%d", &a[i]); memset(dp, 0x3f, sizeof(dp)); sum[0] = 0; for(int i = 1; i <= n; i++) { dp[i][i] = 0; p[i][i] = i; sum[i] = sum[i - 1] + a[i]; } for(int len = 2; len <= n; len++) { for(int i = 1; i + len - 1 <= n; i++) { int j = i + len - 1; for(int k = p[i][j - 1]; k <= p[i + 1][j]; k++) { long long val = dp[i][k] + dp[k + 1][j] + (sum[j] - sum[i - 1]); if(val < dp[i][j]) { dp[i][j]= val; p[i][j] = k; } } } } printf("%lld\n", dp[1][n]); return 0; }