#include <fstream>
#define DIM 2000000001

using namespace std;

ifstream fin("stergeri.in");
ofstream fout("stergeri.out");
short int v[DIM];
int n,m,i,x,y,nr,k;
int main(){
    fin>>n>>m>>k;
    for(i=1;i<=m;i++){
        fin>>x>>y;
        v[x]=1;
        v[y+1]=-1;
    }
    for(i=1;i<=n && nr<k;i++){
        v[i]+=v[i-1];
        if(v[i]==0)
            nr++;
        if(nr==k){
            fout<<i;
            return 0;}
    }
    return 0;
}