#include <bits/stdc++.h>
using namespace std;
#define NMAX 5002
#define MMAX 100001
int g[NMAX], p[NMAX], d[MMAX];
int main(void){
    ofstream cout("rucsac.out");
    ifstream cin("rucsac.in");
    int n, m;
    cin >> n >> m;
    for(int i = 1;i<=n;i++){
        cin >> g[i] >> p[i];
    }
    d[0] = 1;
    int maxim = -1;
    for(int i = 1;i<=n;i++){
        for(int j = m;j>=0;j--){
            if(d[j] != 0 && j + g[i] <= m){
                d[j + g[i]] = max( d[ j + g[i]], d[j] + p[i]);
                maxim = max(maxim, d[j + g[i]]);
            }
        }
    }
    cout << maxim - 1;
}