HackerEarth Roy and Trending Topics problem solution

In this HackerEarth Roy and Trending Topics problem solution, Roy is trying to develop a widget that shows Trending Topics (similar to Facebook) on the home page of HackerEarth Academy.

He has gathered a list of N Topics (their IDs) and their popularity score (say z-score) from the database. Now z-score change every day according to the following rules:

1. When a topic is mentioned in a ‘Post’, its z-score is increased by 50.
2. A ‘Like’ on such a Post, increases the z-score by 5.
3. A ‘Comment’ increases the z-score by 10.
4. A ‘Share’ causes an increment of 20.

Now the Trending Topics are decided according to the change in z-score. One with the highest increment comes on top and the list follows.

Roy seeks your help to write an algorithm to find the top 5 Trending Topics.

If a change in z-score for any two topics is the same, then rank them according to their ID (one with higher ID gets priority). It is guaranteed that IDs will be unique.

#include <iostream>
#include <cstdio>
#include <vector>
#include <algorithm>
#include <utility>
#include <map>
using namespace std;
vector < pair<long long, long long> > topics;
map<long long,long long> id_zscore_map;
int main()
{
    int n;
    long long id, z, p, l, c, s;
    scanf(" %d",&n);
    for(int i=0;i<n;i++)
    {
        scanf(" %lld %lld %lld %lld %lld %lld",&id,&z,&p,&l,&c,&s);
        topics.push_back(make_pair( (p*50 + l*5 + c*10 + s*20 - z) , id));
        id_zscore_map[id] = z;
    }
    make_heap(topics.begin(), topics.end());
    for(int i=0;i<5;i++)
    {
        printf("%lld %lldn",topics.front().second, id_zscore_map[topics.front().second] + topics.front().first);
        pop_heap (topics.begin(),topics.end()); topics.pop_back();
    }
    return 0;
}