#include <cstdio>

#define IN "stergeri.in"
#define OUT "stergeri.out"

using namespace std;

int n , m , k , i;

struct structura

{
    int x , y;
}v [ 100002 ];

void citeste ()

{
    scanf ( "%d%d%d" , &n , &m , &k );

    for ( i = 1 ; i <= m ; i ++ )

        scanf ( "%d%d" , &v [ i ].x , & v [ i ].y );


}

void rezolva()

{
    for ( i = m ; i >= 1 ; i -- )

        if ( k >= v [ i ].x )

            k += ( v [ i ].y - v [ i ].x + 1 );

    printf  ( "%d" , k );
}

int main()
{
    freopen ( IN , "r" , stdin );
    freopen ( OUT , "w" , stdout );

    citeste();
    rezolva();
}