#include <stdio.h>

int main() {
  int a,b,max,T[1001],n,time,wait,go;
  scanf("%d %d", &n, &time);
  for(b=0;b<=time;b++) T[b]=-1;
  T[0]=0;
  max=0;
  for(a=0;a<n;a++) {
    scanf("%d %d", &go,&wait);
    for(b=0;b+wait+go<=time;b++) if(T[b]!=-1) {
      T[b+wait+go] >?= T[b]+go;
      max >?= T[b]+go;
    }
  }
  printf("%d\n", max);
  return 0;
}