#include <stdio.h>
#include <stdlib.h>
#define N 5000
#define K 10000

int profit[K], n, k;

int max(int x, int y)
{
    return (x > y ? x : y);
}

int main()
{
    FILE *in, *out;
    in = fopen("rucsac.in", "r");
    out = fopen("rucsac.out", "w");
    fscanf(in, "%d%d", &n, &k);
    int i, j;
    for (j = 1; j <= k; j++)
    {
        profit[j] = -1;
    }
    for (i = 0; i < n; i++)
    {
        int g, p;
        fscanf(in, "%d%d", &g, &p);
        for (j = k - g; j >= 0; j--)
        {
            if (profit[j] != -1)
            {
                profit[j + g] = max(profit[j + g], profit[j] + p);
            }
        }
    }
    fclose(in);
    int rez = -1;
    for (j = 1; j <= k; j++)
    {
        rez = max(rez, profit[j]);
    }
    fprintf(out, "%d", rez);
    fclose(out);
    return 0;
}