NOI 1995 石子合并

#include<iostream>
#include<cstdio>
#include<cstring>
#include<queue>
#include<algorithm>
#define INF 0x3f3f3f3f
using namespace std;
int f1[2100][2100],f2[2100][2100],a[2100],n,x;
int main()
{
memset(f1,0x3f,sizeof(f1));
memset(f2,0,sizeof(f2));
scanf("%d",&n);
for(int i=1;i<=n;i++)
{
scanf("%d",&x);
a[i]=a[i-1]+x;
f1[i][i]=0;f1[i+n][i+n]=0;
f2[i][i]=0;f2[i+n][i+n]=0;
}
for(int i=1;i<=n;i++)
a[i+n]=a
+a[i];
for(int i=2*n;i>=1;i--)
for(int j=i+1;j<=i+1+n;j++)
for(int k=i;k<j;k++)
{
f1[i][j]=min(f1[i][j],f1[i][k]+f1[k+1][j]+a[j]-a[i-1]);
f2[i][j]=max(f2[i][j],f2[i][k]+f2[k+1][j]+a[j]-a[i-1]);
}
int ans1=INF,ans2=0;
for(int i=1;i<=n;i++)
{
ans1=min(ans1,f1[i][i+n-1]);
ans2=max(ans2,f2[i][i+n-1]);
}
printf("%d\n%d",ans1,ans2);
return 0;
}