#include <fstream.h>  
int main(){  
     unsigned long a[2000000000],n,x,y,i,j,k,m,z;  
     ifstream in("stergeri.in");  
     ofstream out("stergeri.out");  
   
     in>>n>>m>>k;z=m;  
     for(i=1;i<=n;i++)a[i]=i;z=m;  
     for(i=0;i<z;i++){  
         in>>x>>y;  
         for(j=x;j<=y;j++)  
             if(a[j])a[j]=0;  
                 else y++;  
     }  
     for(i=1;i<=n&&k;i++)  
         if(a[i])k--;  
     out<<a[i-1];  
     return 0;  
 }