#include <iostream>
#include <fstream>
#define nmax 100000
using namespace std;
ifstream in ("stergeri.in");
ofstream out ("stergeri.out");

int x[nmax+1], y[nmax+1];

int main()
{
    int n, m, k;
    in>>n>>m>>k;
    for (int i= 1;i<=m;++i)
    {
        in>>x[i]>>y[i];
    }
    for (int i=m;i>0;--i)
    {
        if (k>=x[i])
        {
            k+= -x[i]+y[i]+1;
        }
    }
    out<<k;

    return 0;
}