int main()
{
	int n, i, j;
	int beg,end;
	int pos[20002] = { 0 };
	int num[50000][2] = { 0};
	scanf( "%d",&n);
	for( i = 0; i < n; i ++ )
	{
		scanf( "%d%d",&num[i][0],&num[i][1]);
		for( j = 2 * num[i][0]; j <= 2 * num[i][1]; j ++)
			pos[j] = 1;
	}
	i = 10000;
	while( pos[i] == 0 ) i--;
	end = i;
	i = 0;
	while( pos[i] == 0) i ++;
	beg = i;
	for( i = beg; i <= end; i ++)
	{
		if( pos[i] == 0 )
		{
			printf("no");
			break;
		}
	}
    if( i == end + 1)
	printf( "%d %d", beg/2, end/2);
	return 0;
}
