#include<stdio.h>
using namespace std;

int a[100001],b[100001];
int i,j,k,m,n,u;

int main()
{
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);
    scanf("%d%d%d",&n,&m,&k);
    for (i=1; i<=m; ++i) scanf("%d%d",&a[i],&b[i]);
    int sol=0;
    for (i=m ; i>=1; --i)
        if (k>=a[i]) k+=b[i]-a[i]+1;
    printf("%d",k);
    return 0;

}