/*
ID: xildar91
PROG: humble
LANG: C++11
*/
#include <bits/stdc++.h>
using namespace std;
typedef  long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<ll> vll;
int inf_int=2e9;
ll inf_ll=2e18;
typedef pair<int,int> pii;
#define pb push_back
const double pi=3.1415926535898;
#define dout if(debug) cout
#define fi first
#define se second
#define sp setprecision
#define sz size()
#define x1 gfgs
#define y1 asd
#define rank asdsad
bool debug=0;
const int maxn=1e5+7;


void solve()
{
    ll k,n,m;
    cin >> n >> k >> m;
    int p[n],c[n];
    vector<pair<pii,int> > a;
    for(int i=0;i<n;i++)
    {
        cin >> p[i]>> c[i];
        a.pb({{c[i],0},i});
        a.pb({{p[i],1},i});
    }
    sort(a.begin(),a.end());
    map<int,bool> mp;
    int ans=0;
    set<pair<ll,int> > s;
    set<pair<ll,int> > s1;
    for(int i=0;i<a.sz;i++)
    {
        int in=a[i].se;
        if(a[i].fi.se==0)
        {
            if(k>0)
            {
                if( m >= a[i].fi.fi)
                {
                    k--;
                    mp[in]=true;
                    m=m-a[i].fi.fi;
                    s.insert({p[in]-c[in],in});
                    ans++;
                }


            }
            else
            {
                if(s.begin()->fi + a[i].fi.fi<=m)
                {
                    m=m-(s.begin()->fi + a[i].fi.fi);
                    ans++;
                    int in1=s.begin()->se;
                    s1.insert({-p[in1],in1});
                    mp[in]=true;
                    s.erase(s.begin());
                    s.insert({p[in]-c[in],in});
                }
            }
        }
        else
        {
            if(mp[in])
            {
                continue;
            }
            else if(m>=a[i].fi.fi)
            {
                m=m-a[i].fi.fi;
                ans++;
                mp[in]=true;
            }
            else if(-s1.begin()->fi>a[i].fi.fi)
            {
                m=m+(-s1.begin()->fi-a[i].fi.fi);
                s1.erase(s1.begin());
                s1.insert({-a[i].fi.fi,in});
            }
        }
    }
    cout << ans;


}






#define FILE "B-large"
int main()
{

     //   freopen("input.txt","r",stdin);
     //   freopen("output.txt","w",stdout);

        // freopen(FILE".in","r",stdin);
       // freopen(FILE".out","w",stdout);
       if(!debug)
       {
            ios_base::sync_with_stdio(0);
            cin.tie(0);
            cout.tie(0);
       }
        int t=1;
        while(t--)
            solve();
        return 0;
}