#include <iostream>
#include <algorithm>
#define int long long
using namespace std;
struct node {
	int w,v;
} obj[5010];
int dp[5010][1001000];
int f[5010];
bool cmp(node a,node b) {
	if(a.w==b.w) return a.v>b.v;
	return a.w<b.w;
}
bool cmp2(int a,int b){
	return a>b;
}
signed main() {
	int n,w,k;
//	freopen("knapsack8.in","r",stdin);
	cin>>n>>w>>k;
	for(int i=1; i<=n; i++) {
		cin>>obj[i].w>>obj[i].v;
	}
	sort(obj+1,obj+1+n,cmp);
	for(int i=1; i<=n; i++) {
		for(int j=0; j<=w; j++) {
			if(j-obj[i].w>=0)
			dp[i][j]=max(dp[i-1][j],dp[i-1][j-obj[i].w]+obj[i].v);
		}
	}
	int res=0;
	int temp=0;
	int idx=0;
	for(int i=n;i>=0;i--){
		temp=dp[i][w];
		idx++;
		f[idx]=obj[i+1].v;
		for(int j=idx;j>1;j--){
			if(f[j]>f[j-1]) swap(f[j],f[j-1]);
			else break;
		}
		for(int j=1;j<=min(idx,k);j++){
			temp+=f[j];
		} 
		res=max(res,temp);
	}
	cout<<res;
	return 0;
}
//	f[1]=0;
/*
5 13 2
5 16
5 28
7 44
8 15
8 41


*/

/tmp/ccxTnrvb.o: in function `main':
answer.code:(.text.startup+0x59): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0xb2): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0xc0): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0xf0): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x139): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x14e): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x1a6): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x21a): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x26b): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x44d): relocation truncated to fit: R_X86_64_PC32 against symbol `obj' defined in .bss section in /tmp/ccxTnrvb.o
answer.code:(.text.startup+0x465): additional relocation overflows omitted from the output
collect2: error: ld returned 1 exit status