// editor2
#include <stdio.h>
#include <stdlib.h>

#define MAX  101

int queue[MAX], front =-1,rear = -1;
int visited[MAX] = {0};
int adj[MAX][MAX]= {0};

void enqueue(int val)
{
    if (rear == MAX -1)
    {
        return;
    }
    if (front == -1)
    {
        front =0;
    }
    queue[++rear]=val;
}
int dequeue()
{
    if (front == -1 || front>rear)
    {
        return -1;
    }
    return queue[front++];
}
int isEmpty()
{
    return (front == -1 || front>rear);
}
int main()
{
    int n,m;
    scanf("%d %d",&n, &m);
    if(n<=0 || m<0)
    {
        printf("Invalid input");
        return 0;
    }
    for (int i =0;i<m;I++)
    {
        int u,v;
        scanf("%d %d",&u ,&v);
        if(u<=0 || v<=0)
        {
            printf("Invalid inpur");
            return 0;
        }
        if(u>n || v>n)
        {
            printf("Invalid input");
        }
        adj[u][v] = 1;
        adj[][]
    }
}