usaco08mar river crossing

#include <cstdlib>
#include <algorithm>
#include <cstring>
#include <cctype>
#define INF 2000000000
using namespace std;
typedef long long ll;
int sum[2505],n,f[2505]={0};
int (){
    int f=1,x=0;char c=getchar();
    while(c<'0'||c>'9'){if(c=='-')f=-f;c=getchar();}
    while(c>='0'&&c<='9')x=x*10+c-'0',c=getchar();
    return f*x; 
}    
void init(){
    scanf("%d%d",&n,&sum[0]);
    for(int i=1;i<=n;i++)
        scanf("%d",&sum[i]),
        sum[i]+=sum[i-1];
}
void solve(){
    fill(f,f+n+1,INF);
    f[0]=0;
    for(int i=1;i<=n;i++)
        for(int j=i-1;j>=0;j--)
            f[i]=min(f[i],f[j]+sum[i-j]+sum[0]);
    printf("%dn",f[n]-sum[0]);
}
int main(){
    init();
    solve();
    return 0;
}