Euler 186

#include <iostream>
#define N 1000000
using namespace std;
struct node{
    int rank;
    int num_of_friends;
    node *parent;
};
int generateNum[100000000];
//-------------------------
node * makeSet();

//---------------------------
node *findSet(node *x);

//------------------------------
int GetCallerId(int k);

//--------------------------
void unite(node *x,node *y);

int GetCalledId(int k);

int main() {
    node **clients=new node *[N];
    for(int i=0;i<N;i++){
        clients[i]=makeSet();
    }
    node *MD=clients[524287];
    int counter=0;
    int num=1;
    int caller,called;
    while(findSet(MD)->num_of_friends<990000){
        caller=GetCallerId(num);
        called=GetCalledId(num);
        if (caller!=called) {
            unite(clients[caller],clients[called]);
            counter++;
        }
        num++;
        if(num%1000==0) cout<<findSet(MD)->num_of_friends<<endl;
    }
    cout<<"num of friends of PM:"<<findSet(MD)->num_of_friends<<endl;
    cout<<"num of succesful calls:"<<counter<<endl<<"num of all calls:"<<num;
    delete[] clients;
    return 0;
}
//-------------------------
node * makeSet(){
    node * v = new node;
    v->num_of_friends=1;
    v->parent=v;
    v->rank=0;
    return v;
}
//---------------------------
node *findSet(node *x){
    if (x->parent == x) {
        return x;
    }
    else {
        return x->parent = findSet(x->parent);
    }
}
//--------------------------
void unite(node *x,node *y){
    node *Rx=findSet(x);
    node *Ry=findSet(y);
    if(Rx==Ry) return;
    else{
        if(Rx->rank < Ry->rank){
            Rx->parent=Ry;
            Ry->num_of_friends+=Rx->num_of_friends;
        }
        else{
            Ry->parent=Rx;
            Rx->num_of_friends+=Ry->num_of_friends;
            if(Ry->rank==Rx->rank) Rx->rank++;
        }
    }
    return;
}
//------------------------------
int GetCallerId(int k){
    unsigned long long int number;
    k=(2*k)-1;
    if(k<=55){
        number= (unsigned long long int) (k * k * k * 300007);
        number-=k*200003;
        number+=100003;
        number%=1000000;
        generateNum[k]= (int) number;
        return (int) number;
    }
    else{
        number= (unsigned long long int) ((generateNum[k-24] + generateNum[k-55]) % 1000000);
        generateNum[k]= (int) number;
        return (int) number;
    }
}
int GetCalledId(int k){
    unsigned long long int number;
    k=2*k;
    if(k<=55){
        number= (unsigned long long int) (k * k * k * 300007);
        number-=k*200003;
        number+=100003;
        number%=1000000;
        generateNum[k]= (int) number;
        return (int) number;
    }
    else{
        number= (unsigned long long int) ((generateNum[k-24] + generateNum[k-55]) % 1000000);
        generateNum[k]= (int) number;
        return (int) number;
    }
}