#include<bits/stdc++.h>
using namespace std;
struct jie{
	int jia;
	int liang;
};
jie a[1000005];
int main(){
	int n,m,sum = 0,ans = 0;
	cin>>n>>m;
	for(int i = 0;i<n;i++){
		cin>>a[i].jia>>a[i].liang;
	}
	sort(a,a+n);
	for(int i = 0;i<n;i++){
		sum+=a[i].jia;
		ans+=a[i].liang;
		if(ans>=m){
			cout<<sum;
			return 0;
		}
	}
	cout<<"no solution";
	return 0;
}