题目链接：点击打开链接

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <vector>
#include <iostream>
#include <map>
#include <set>
#include <math.h>
using namespace std;
#define inf 1152921504606846976
#define ll __int64
#define N 2005
ll n;
ll dp[N<<1], c[N], t[N];
int main(){
	ll i, j;
	while(cin>>n) {
		for(i=1;i<=n;i++) {
			cin>>t[i]>>c[i];
			t[i]++;
			dp[i] = inf;
		}
		ll sum = inf;
		for(i=1;i<=n;i++)
		{
			for(j=n;j>=0;j--)
				if(dp[j] != inf || !j)
				{
					if(j+t[i]<n)
						dp[j+t[i]] = min(dp[j + t[i]], dp[j]+c[i]);
					else 
						sum = min(sum, dp[j]+c[i]);
				}
		}
		cout<<sum<<endl;
	}
	return 0;
}