#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("stergeri.in");
ofstream fout("stergeri.out");

struct interval
{
    long long int x, y;
}v[100002];

long long int n, m, k;

int main()
{
    fin >> n >> m >> k;
    
    for(int i = 1; i <= m; i++)
        fin >> v[i].x >> v[i].y;
        
    for(int i = m; i >= 1; i--)
    {
        if(k >= v[i].x)
            k += v[i].y - v[i].x + 1;
    }
    fout << k;
    return 0;
}