#include <bits/stdc++.h>

using namespace std;

ifstream ci ("stergeri.in");
ofstream co ("stergeri.out");

struct stergeri
{
    int x, y;
}a[100001];

int main()
{
    int n, m, k;
    ci >> n >> m >> k;
    for (int i=1; i<=m; i++)
    {
        ci >> a[i].x >> a[i].y;
    }
    for (int i=m; i>0; i--)
    {
        if (k>=a[i].x)
        {
            k+=a[i].y-a[i].x+1;
        }
    }
    co << k;
    return 0;
}