#include <bits/stdc++.h>
using namespace std;
ifstream fin("rucsac.in");
ofstream fout("rucsac.out");
int n,G,costmax,cost,greu;
short x[100],y[100];
struct obiect
{
    int g,c;
}v[100];
void verif()
{
    cost=0;
    for(int i=1;i<=n;i++)
        cost=cost+x[i]*v[i].c;
    if(cost>costmax)
    {
        costmax=cost;
        for(int j=1;j<=n;j++)
            y[j]=x[j];
    }
}
void read()
{
    fin>>n>>G;
    for(int i=1;i<=n;i++)
        fin>>v[i].c>>v[i].g;
}
void back(int k)
{
    if(k>n)
        verif();
    else
    {
        x[k]=1;
        greu=greu+v[k].g;
        if(greu<=G)
            back(k+1);
        greu=greu-v[k].g;
        x[k]=0;
        back(k+1);
    }
}
int main()
{
    int cmax=0;
    read();
    back(1);
    for(int i=1;i<=n;i++)
        if(y[i]==1)
            cmax=cmax+v[i].c;
    fout<<cmax;
    return 0;
}