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

int n, t, p[1000], nr, cnt;

typedef struct
{
	int c, v;
} mistret;
mistret v[20];

int cmp(const void *a, const void *b)
{
	return *(int*)a - *(int*)b;
}

void citire()
{
	freopen("vanatoare.in","r",stdin);
	freopen("vanatoare.out","w",stdout);

	int i;
	scanf("%d %d",&n,&t);

	printf("%d\n",n);

	for (i = 1; i <= n; i++)
	{
		scanf("%d %d",&v[i].c, &v[i].v);
		printf("%d ",v[i].c);
}



int main()
{
	citire();
	return 0;
}