#include <iostream>
#include <fstream>
#include <algorithm>
#include <cmath>
using namespace std;


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

int n,m,k;

pair <int,int>a[100002];

int main()
{
    int i;
    f>>n>>m>>k;
    for(i=1;i<=m;i++)
        f>>a[i].first>>a[i].second;



     int x,y;
    for(i=m;i>=1;i--)
    {
        x = a[i].first;
        y = a[i].second;
        if(k >= x)
            k += y-x+1;
    }
    g<<k<<"\n";

    return 0;
}