#include <bits/stdc++.h> 
using namespace std;
struct Drink{
	int c,l;
}a[514];
bool cmp(Drink A,Drink B){
	return A.c<B.c;
}
int main(){
	int n,L,deadcnt=0;cin>>n>>L;
	for(int i=1;i<=n;i++){
		cin>>a[i].c>>a[i].l;
		deadcnt+=a[i].l;	
	}
	if(deadcnt<L){cout<<"no solution";return 0;}
	sort(a+1,a+n+1,cmp);
	int lcnt=0,i=1,cnt=0;
	while(lcnt<L){
		lcnt+=a[i].l;
		cnt+=a[i].c;
		i++;
	}
	if(cnt==0){cout<<"no solution";return 0;}
	cout<<cnt;
}