#include <fstream>
#include <iostream>

#define mmax 100005

using namespace std;

ifstream f("stergeri.in");
ofstream g("stergeri.out");

int n, m, k;
struct{

    int x, y;

}a[mmax];

void citeste(){

    f >> n >> m >> k;

    for(int i=1; i<=m; i++) f >> a[i].x >> a[i].y;

}

void rezolva(){

    for(; m; --m){
        if (k >= a[m].x) k += a[m].y - a[m].x + 1;
    }

    g << k << "\n";

}

int main(){

    citeste();
    rezolva();

    f.close();
    g.close();

    return 0;

}