#include <bits/stdc++.h>

using namespace std;

ifstream fin("stergeri.in");
ofstream fout("stergeri.out");
struct
{
    int x,y;
}v[100005];
int n,m,k,i;
int main()
{
    fin>>n>>m>>k;
    for(i=1;i<=m;i++)
        fin>>v[i].x>>v[i].y;
    for(i=m;i>=1;i--)
        if(k>=v[i].x)
            k=k+v[i].y-v[i].x+1;
    fout<<k;
    return 0;
}