#include<stdio.h>
using namespace std;
#define dim 100001

long long v[dim],w[dim];

int main()
{
	long long i=0,n=0,m=0,k=0,x=0,y=0;
FILE *f=fopen("stergeri.in","r"), *g=fopen("stergeri.out","w");

fscanf(f,"%lld%lld%lld",&n,&m,&k);
for(i=1;i<=m;i++)
	{
		fscanf(f,"%lld%lld",&v[i],&w[i]);
		//if(x<=k) k+=y-x+1-(k-x);
	
	}
for(i=m;i>=1;i--)
	{
		if(v[i]<=k)
			k+=w[i]-v[i]+1;	
	}



fprintf(g,"%lld\n",k);

fclose(f);
fclose(g);
return 0;
}