#include<fstream>
#include<queue>
#include<algorithm>
using namespace std;
ifstream fin("peste.in");
ofstream fout("peste.out");
struct plasa{
    int timp;
    int pesti;
};
int cmp(plasa a,plasa b){
    if(a.timp==b.timp){
        return a.pesti<=b.pesti;
    }
    else{
        return a.timp<=b.timp;
    }
}
int i,j,n,k,t,r;
long long s;
long long aux[50005],sol[50005];
plasa v[50005];
priority_queue< int, vector<int>, greater<int> > q;
int main(){
    fin>>n>>k>>t;
    for(i=1;i<=n;i++){
        fin>>v[i].pesti>>v[i].timp;
    }
    sort(v+1,v+n+1,cmp);
    s=0;
    for(i=1;i<=n;i++){
        s+=v[i].pesti;
        q.push(v[i].pesti);
        if(q.size()>k){
            s-=q.top();
            q.pop();
        }
        if(s>=aux[v[i].timp]){
            aux[v[i].timp]=s;
        }
    }
    for(i=1;i<=t;i++){
        r=min(i,1000);
        for(j=0;j<=r;j++){
            sol[i]=max(sol[i],sol[j]+aux[i-j]);
        }
    }
    fout<<sol[t];
    return 0;
}