#include<cstdio>
using namespace std;

FILE *f=fopen ("stergeri.in","r");
FILE *g=fopen("stergeri.out","w");

int v[100100],w[100100];
int main(){
	int n,m,i,k;
	fscanf (f,"%d%d%d",&n,&m,&k);
    for(i=1;i<=m;++i){
       fscanf (f,"%d%d",&v[i],&w[i]);
    }
    for(i=m;i>=1;--i){
        if(k>=v[i]){
            k+=w[i]-v[i]+1;
		}
    }
	fprintf (g,"%d",k);
	
    return 0;
}