#include <cstdio>
#include <algorithm>
using namespace std;
int k;
void solve(int a,int b,int m)
{
    if(m!=0)
    {
        int x,y;
        scanf("%d%d",&x,&y);
        solve(x,y,m-1);
    }
    if(k>=a && a!=0)
        k+=(b-a+1);
}
int main()
{
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);
    int n,m;
    scanf("%d%d%d",&n,&m,&k);
    solve(0,0,m);
    printf("%d",k);
    return 0;
}