//
//  main.cpp
//  stergeri
//
//  Created by Alex Petrache on 03/06/14.
//  Copyright (c) 2014 Alex Petrache. All rights reserved.
//

#include <iostream>
#include <fstream>
using namespace std;
int main(int argc, const char * argv[])
{
    int n,m,k,i,a[100009],b[100009];
  //  ifstream f("/Users/alexpetrache/Documents/Programare/Xcode/stergeri/stergeri/stergeri.in");
//    ofstream g("/Users/alexpetrache/Documents/Programare/Xcode/stergeri/stergeri/stergeri.out");
    ifstream f("stergeri.in");
    ofstream g("stergeri.out");
    f>>n>>m>>k;
    for(i=0;i<m;i++)
        f>>a[i]>>b[i];
    for(i=m-1;i>=0;i--){
        if(k>=a[i])
            k+=b[i]-a[i]+1;
    }
    g<<k;
    return 0;
}