UVA 10304 Optimal Binary Search Tree

#include<cstdio>
#include<cstring>
#include<cmath>
#include<vector>
#include<map>
#include<queue>
#include<stack>
#include<algorithm>
using namespace std;

const int maxn = 300;
int n;
int a[maxn], sum[maxn], dp[maxn][maxn];

int main()
{
while (~scanf("%d", &n))
{
sum[0] = 0;
for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
for (int i = 1; i <= n; i++) sum[i] = sum[i - 1] + a[i];

memset(dp, 0, sizeof dp);

for (int i = 2; i <= n; i++)
{
for (int j = 1; j+i-1 <= n; j++)
{
int st = j, en = j + i - 1;
int ans = 0x7FFFFFFF;
for (int k = st; k <= en; k++)
ans = min(dp[st][k - 1] + dp[k + 1][en] + sum[en] - sum[st - 1] - a[k],ans);
dp[st][en] = ans;
}
}
printf("%d\n", dp[1]
);
}
return 0;
}