#include <bits/stdc++.h>

using namespace std;
ifstream f("stergeri.in");
ofstream g("stergeri.out");
struct interval
{
  int x, y;
} v[100005];
int n, m, k;

void Read()
{
  f>>n>>m>>k;
  for(int i = 1;i <= m;++i)
    f>>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;
  g<<k;
}

int main()
{
  Read();
  return 0;
}