link to question is Harmo and tools first join group ACM-OI if u face any difficulities in accessing problem.

My Code:[submission:13129913]

#include<bits/stdc++.h>
#define ll long long int
#define inp(x) scanf("%lld",&x)
using namespace std;
struct node{
    ll d;
    node * next;
};
struct hdnode{
    node * next;
};
struct ds{
    hdnode * head;
    node * tail;
};
ds *a;
static ll szt[100009];
inline void pre(ll n){
    a =  new ds [100009];
    for(ll i=1;i<=n;++i){
        a[i].head = new hdnode;
        a[i].tail = new node;
        (a[i].tail)->d = i;
        (a[i].tail)->next = NULL;
        (a[i].head)->next = a[i].tail;
    }
    return ;
}
inline void finds(ll n){
    for(ll i=1;i<=n;++i){
        if(a[i].head!=NULL){
            node *temp = new node;
            temp = (a[i].head)->next;
            while(temp!=NULL){
                szt[temp->d] = i;
                temp = temp->next;
            }
        }
    }
    return ;
}
inline void merges(ll s,ll t){
    if(a[s].head == NULL){
        return ;
    }
    (a[t].tail)->next = (a[s].head)->next;
    a[s].head = NULL;
    a[t].tail = a[s].tail;
    //a[s].tail = NULL;
    return ;
}
int main(){
    ll n,q,s,t;
    inp(n);inp(q);
    pre(n);
    while(q--){
        inp(s);inp(t);
        merges(s,t);
        /* snippet for checking
        for(ll i=1;i<=n;++i){
                cout<<i<<" : ";
        if(a[i].head!=NULL){
            node *temp = new node;
            temp = (a[i].head)->next;
            while(temp!=NULL){
                cout<<temp->d<<" ";
                temp = temp->next;
            }
        }
        cout<<endl;
    }*/

    }
    finds(n);
    for(ll i=1;i<=n;++i){
        printf("%lld ",szt[i]);
    }
    return 0;
}