Disjoint Set Union

#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;

#define si(n) scanf("%d",&n)
#define MAX 10004

int parent[MAX],rnk[MAX];


void make_set (int v) {
    parent[v] = v;
    rnk[v] = 0;
}

int find_set (int v) {
    if (v == parent[v])
        return v;
    return parent[v] = find_set (parent[v]);
}

void union_sets (int a, int b) {
    a = find_set (a);
    b = find_set (b);
    if (a != b) {
        if (rnk[a] < rnk[b])
            swap (a, b);
        parent[b] = a;
        if (rnk[a] == rnk[b])
            ++rnk[a];
    }
}

int main(){
    int n,m,i,j;
    //freopen("input.txt","r",stdin);
    si(n);si(m);
    for(i=1;i<=n;i++)
        make_set(i);
    for(i=1;i<=m;i++){
        int u,v;
        si(u);si(v);
        union_sets(u,v);
    }
    for(i=1;i<=10;i++){
        int u,v;
        si(u);si(v);
        if(find_set(u)!=find_set(v))
            cout<<"Not friend"<<endl;
        else cout<<"Friend"<<endl;
    }
    return 0;
}