Help needed with priority queue custom comparator

Revision en1, by decoder__, 2020-05-17 18:49:09
#include <bits/stdc++.h>
#define fastio        ios_base::sync_with_stdio(false); cin.tie(NULL);
#define ln            cout<<endl;
#define vi            vector<int>
#define vll           vector<long long>
#define sortl(vec)    sort(vec.begin(), vec.end());
#define sortr(vec)    sort(vec.rbegin(), vec.rend());
#define forn(i, x, n) for(int i = x; i < int(n); i++)
#define in(vec)       for(auto &it : vec) cin>>it;
#define loop(vec)     for(auto &it : vec)
#define	out(vec)      for(auto &it : vec) cout<<it<<" ";
#define ll            long long
#define mod           1000000007
#define debug(x)      cout << x << endl;
#define pb			  push_back
#define mp            make_pair
#define um			  unordered_map
#define pii			  pair<int, int>
#define pll           pair<ll, ll>
#define f             first
#define s             second
#define dp3d(n)       vector<vector<vector<ll>>>dp(n, vector<vector<ll>>(n, vector<ll>(n)));
using namespace std;

ll power(ll x, ll y, ll p) {
	ll res = 1;
	x = x % p;

	while (y > 0) {
		if (y & 1)
			res = (res * x) % p;

		y = y >> 1;
		x = (x * x) % p;
	}
	return res;
}

ll modulo(ll a, ll b) {
	ll c = a % b;
	return (c < 0) ? c + b : c;
}

struct cmp {

	bool operator()(const pair<ll, pll> &p1, const pair<ll, pll> &p2) const {


		if (p1.f == p2.f)
			return p1.s.f < p2.s.f;

		return p1.f > p2.f;

	}
};

int main() {

#ifndef ONLINE_JUDGE
	// for getting input from input.txt
	freopen("input1.txt", "r", stdin);
	// for writing output to output.txt
	freopen("output1.txt", "w", stdout);
#endif

	fastio
	ll t;
	cin >> t;
	while (t--) {
		ll n;
		cin >> n;
		vll ans(n + 1);
		priority_queue < pair<ll, pll>, vector<pair<ll, pll>>, cmp>pq;
		pair<ll, pll> m;
		pq.push(mp(n, mp(1, n)));
		forn(i, 1, n + 1) {
			m = pq.top();
			pq.pop();
			ll mid = (m.s.f + m.s.s) / 2;
			ans[mid] = i;
			if (mid - 1 >= m.s.f) {
				pq.push(mp(mid - m.s.f, mp(m.s.f, mid - 1)));
			}
			if (mid + 1 <= m.s.s) {
				pq.push(mp(m.s.s - mid, mp(mid + 1, m.s.s)));
			}
			//cout << pq.top().f << endl;
			//cout << pq.top().s.f << " " << pq.top().s.s << endl;

		}

		forn(i, 1, n + 1)
		cout << ans[i] << " ";
		ln

	}
	return 0;
}

Here is pair structure pair<long long , pair<long, long>> I want the pair with largest first element on the top of the priority queue, if first element is same the check for the smallest first element in the second pair. But my code is doing the reverse.

I'm working out this code for the question https://codeforces.me/contest/1353/problem/D

Please help

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en1 English decoder__ 2020-05-17 18:49:09 2697 Initial revision (published)