#include <stdio.h>

typedef struct {
    int g;
    int s;
} obiect;

int max(obiect t[],int n,int gl,int s,int i,int g){
    int maxim=0;
    if(gl==g)return s;
    for(i;i<n;i++){
        if(gl+t[i].g<=g){
            int ml=max(t,n,gl+t[i].g,s+t[i].s,i+1,g);
            if(maxim<ml)maxim=ml;
        }
    }
    return maxim;
}

int main()
{
    int n,g;
    int i=0;
    FILE *f=fopen("rucsac.in","rt");
    fscanf(f,"%d %d",&n,&g);
    obiect t[n];
    for(i=0;i<n;i++){
        fscanf(f,"%d %d",&t[i].g,&t[i].s);
    }
    close(f);
    f=fopen("rucsac.out","wt");
    fprintf(f,"%d",max(t,n,0,0,0,g));
    close(f);

    return 0;
}