#include <stdio.h>
#include <stdlib.h>

int indici[2][100000];

int main() {
    FILE *fin, *fout;
    int n, m, k, i;
    fin = fopen( "stergeri.in", "r" );
    fout = fopen( "stergeri.out", "w" );
    fscanf( fin, "%d%d%d", &n, &m, &k );
    for ( i = 0; i < m; i++ )
        fscanf( fin, "%d%d", &indici[0][i], &indici[1][i] );
    for ( i = m - 1; i >= 0; i-- )
        if ( indici[0][i] <= k )
            k += ( indici[1][i] - indici[0][i] + 1 );
    fprintf( fout, "%d", k );
    fclose( fin );
    fclose( fout );
    return 0;
}