#include <fstream>

using namespace std;
ifstream f("energii.in");
ofstream g("energii.out");
int n,gmax,i,j,ma,gr[10001],v[10001],b[10001];
int main()
{
    f>>n;
    f>>gmax;
    for(i=1;i<=n;++i)
        f>>gr[i]>>v[i];
    b[0]=1;
    for(i=1;i<=n;++i)
    {
        for(j=gmax-gr[i];j>=1;--j)
        if(b[j]!=0 && b[j+gr[i]]<b[j]+v[i])
            b[j+gr[i]]=b[j]+v[i];
        if(v[i]>b[gr[i]])
            b[gr[i]]=v[i];
    }
    ma=0;
    for(i=1;i<=gmax;++i)
        if(b[i]>ma)
        ma=b[i];
    g<<ma;

    return 0;
}