#include <iostream>
#include <fstream>
#define MMAX 100000

using namespace std;

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

struct str {
    int st, l;
} q[MMAX];

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