#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

int main()
{
    ifstream in("stergeri.in");
    ofstream out("stergeri.out");
int n,m,k;
in>>n>>m>>k;
vector<pair<int,int> > stergeri;

for(int i=0;i<m;i++){
    int aux1,aux2;
    in>>aux1>>aux2;
    stergeri.push_back(make_pair(aux1,aux2));
}
int p=k;
for(int i=m-1;i>=0;i--){
    if(p>=stergeri[i].first)p+=stergeri[i].second-stergeri[i].first+1;


}
out<<p;

in.close();
out.close();
    return 0;
}