#include <fstream>
using namespace std;
ifstream fin("stergeri.in");
ofstream fout("stergeri.out");

int n, m, k, st[100010], dr[100010], i;

int main(){
    fin>>n>>m>>k;
    for(i=1; i<=m; i++){
        fin>>st[i]>>dr[i];
    }
    for(i=m; i>0; i--){
        if(k>=st[i]){
            k+=dr[i]-st[i]+1;
        }
    }
    fout<<k;
}