#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <algorithm>
#include <string.h>
#define N 50100
#define INF -1


using namespace std;


struct plasa {
    int p , t ;
};

plasa pls [ N ] ;
int fish [ N ] ;
int best [ N ] ;
long long sol [ N ];

bool cmp ( plasa a , plasa b ){
    return a.t < b.t ;
}


int main(){
    int n , k , tmax , i , j ,id ;
    int sum = 0  , temp ;

    freopen("peste.in","r",stdin );
    freopen("peste.out","w",stdout );

    scanf("%d%d%d", &n , &k , &tmax );

    for ( i = 0 ; i < n ; i ++ ){
        scanf("%d%d",&pls[ i ].p , &pls [ i ].t );
    }


    sort ( pls , pls + n , cmp );

    for ( i  = 0 ; i < n ; i ++ ){

        j = i ;
        fish [ j ] = pls[i].p ;
        if ( j < k ){
            sum += fish [ j ];
        }

        while ( j > 0 && fish [ j ] > fish [ j - 1 ] ){

            if ( j == k ){
                sum = sum + fish [ k ] - fish [ k - 1 ];
            }

            temp = fish [ j ];
            fish [ j ] = fish [ j - 1 ];
            fish [ j - 1 ]= temp ;

            j-- ;
        }

        best [ i ] = sum ;

    }

    for ( i = 0 ; i <= tmax ; i ++ ){
        sol [ i ] = INF ;
    }

    sol [ 0 ] = 0 ;
    for ( i = 0 ; i <  n ; i  ++ ){

        for ( j = tmax - pls [ i ] .t ; j >=0 ; j -- ){

            if ( sol [ j ] == INF ){
                continue ;
            }

            if ( sol[ j + pls [ i ].t ] < sol [ j ] + best [ i ] ){
                sol[ j + pls [ i ].t ] = sol [ j ] + best [ i ] ;
            }

            for ( id = j + 2 * pls [ i ].t  ; id < tmax ; id += pls [ i ].t ){

                if ( sol [ id ] < sol [ id - pls[ i ].t ] ){
                    sol [ id ] = sol [ id - pls[ i ].t ];
                }else {
                    break ;
                }

            }

        }

    }


    for ( i = 0 ; i <= tmax ; i ++ ){
        sol[ tmax ] = max ( sol [ i ] , sol [ tmax ] ) ;
    }


    if ( sol [ tmax ] == -1 ){
        printf("0");
        return 0 ;
    }

    printf("%lld",sol[ tmax ] );

    return 0;
}