#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("stergeri.in");
ofstream fout("stergeri.out");
#define MAX 100003

struct sebi{
    int i, j;
}a[MAX];


int main()
{
    int m, n, k, i;
    fin >> n >> m >> k;
    for (i = 1; i <= m ; i++)
    {
        fin >> a[i].i >> a[i].j;
    }
    for(i = m ; i >= 1 ; i--){
        if(k >= a[i].i){
            k += (a[i].j - a[i].i + 1);
        }
    }
    fout << k << "\n";


}