#include<fstream>
#define nmax
using namespace std;
int a[100005],b[100005];
int main(void){
    ifstream fin("stergeri.in");
    ofstream fout("stergeri.out");
    int n,m,k,i;
    fin>>n>>m>>k; 
    for(i=1;i<=m;++i)fin>>a[i]>>b[i];
    for(i=m;i>=1;--i)               
               if(k>=a[i])k+=b[i]-a[i]+1;                          
    fout<<k;
 return 0;   
}