1617: [Usaco2008 Mar]River Crossing渡河问题

#include<iostream>
#include<cstdio>
using namespace std;
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9'){x*=10;x+=ch-'0';ch=getchar();}
return x*f;
}
int n,m[2501],f[2501];
int main(){
n=read();m[0]=read();
for(int i=1;i<=n;i++)m[i]=read()+m[i-1];
for(int i=1;i<=n;i++){
f[i]=0x7fffffff;
for(int j=1;j<=i;j++)
f[i]=min(f[i],f[i-j]+m[j]+m[0]);
}
printf("%d",f
-m[0]);
return 0;
}