#include <iostream>
#include <fstream>
#define nmax 5005
#define inf 10005
using namespace std;
ifstream f("energii.in");
ofstream g("energii.out");
int i,j,n,G,sol;
int v[nmax],w[nmax],m[inf];
int main(){
    f>>n>>G;
    for(i=1;i<=n;i++){
        f>>w[i];
        f>>v[i];
    }
    for(i=0;i<=G;i++){
        m[i]=20000;
    }
    for(i=1;i<=n;i++){
        for(j=G;j>=0;j--){
            if(w[i]<j){
                m[j]=min(m[j],m[j-w[i]]+v[i]);
            }
            else{
                m[j]=min(m[j],v[i]);
            }
        }
    }
    //if(m[G]!=20000){
        //g<<m[G];
    //}
    //else{
        //g<<-1;
    //}
}