#include<cstdio>
#include<algorithm>
#define MAXM 100010
using namespace std;
pair<int,int> v[MAXM];
int main(){
    freopen("stergeri.in","r",stdin);
    freopen("stergeri.out","w",stdout);
    int n,m,k,i;
    scanf("%d%d%d",&n,&m,&k);
    for(i=1;i<=m;i++)
        scanf("%d%d",&v[i].first,&v[i].second);
    for(i=m;i>=1;i--)
        if(k>=v[i].first)
            k=k+v[i].second-v[i].first+1;
    printf("%d",k);
    return 0;
}