#include<fstream>
using namespace std;
ifstream f("stergeri.in");
ofstream g("stergeri.out");
int n,m,x[100100],y[100100],k,i;
int main()
{
    f>>n>>m>>k;
    for(i=1;i<=m;++i)
    {
        f>>x[i]>>y[i];
    }
    for(i=m;i>=1;--i)
    {
        if(k>=x[i])
            k+=y[i]-x[i]+1;
    }
    g<<k;
    return 0;
}