#include <fstream>
#define NMAX 10005

using namespace std;

FILE* f=freopen("rucsac.in","r",stdin);
FILE* o=freopen("rucsac.out","w",stdout);

int n,k;
int d[NMAX];
int w[5005],p[5005];

inline int maxim(int a, int b)
{
    return (a>b)?a:b;
}

int main()
{
    scanf("%d%d",&n,&k);

    for(int i=1;i<=n;++i)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        w[i]=x;
        p[i]=y;
    }

    for(int i=1;i<=k;++i)
    {
        for(int j=1;j<=n;++j)
        {
            if(i-w[j]>=0)
                d[i]=maxim(d[i-1],d[i-w[j]]+p[j]);
        }
    }

    printf("%d",d[k]);

    return 0;
}