#include <bits/stdc++.h>

using namespace std;

int a[100001], b[100001], m, n, k;

void Citire()
{
    int i;
    ifstream fin("stergeri.in");
    fin >> n >> m >> k;
    for(i = 1; i <= m; ++i)
        fin >> a[i] >> b[i];
    fin.close();
}

int Solutie()
{
    int i;
    for(i = m; i >= 1; i--)
        if(k >= a[i])
            k += (b[i] - a[i] + 1);
    return k;
}

int main()
{
    Citire();
    ofstream fout("stergeri.out");
    fout << Solutie();
    fout.close();
    return 0;
}