#include <fstream>

using namespace std;
ifstream cin("energii.in");
ofstream cout("energii.out");
int i,n,j,ma,gmax,g[101],b[1001],v[1001];
int main()
{
    cin>>n;
    cin>>gmax;
    for(i=1;i<=n;++i)
        {
            cin>>g[i];
            cin>>v[i];
        }
    b[0]=1;
    ma=0;
    for(i=1;i<=n;++i)
        {for(j=gmax-g[i];j>=1;--j)
            if((b[j]!=0&&b[j+g[i]]==0)||(b[j+g[i]]<b[j]+v[i]))
        b[j+g[i]]=b[j]+v[i];
    if(v[i]>b[g[i]])
        b[g[i]]=v[i];}
    for(i=1;i<=gmax;++i)
        if(b[i]>ma)
    {
        ma=b[i];
    }
    cout<<ma<<'\n';
    return 0;
}