Submission #804495

#	Time	Username	Problem	Language	Result	Execution time	Memory
804495		faruk	Arranging Shoes (IOI19_shoes)	C++17	45 / 100	41 ms	9536 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define mp make_pair
#define all(a) a.begin(), a.end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pii;

struct seggy {
	int n;
	vector<ll> t;

	seggy(ll siz) {n = siz, t.resize(2*n);}

	ll query(int l, int r) {
		ll out = 0;
		for (l += n, r += n+1; l < r; l /= 2, r /= 2) {
			if (l & 1)
				out += t[l++];
			if (r & 1)
				out += t[--r];
		}
		return out;
	}

	void upd(int idx, int val) {
		idx += n;
		while (idx > 0)
			t[idx] += val, idx /= 2;
	}
};

ll count_inv(vector<ll> perm) {
	seggy seg(perm.size());
	ll out = 0;
	for (int i = 0; i < perm.size(); i++) {
		out += seg.query(perm[i], perm.size() - 1);
		seg.upd(perm[i], 1);
	}
	return out;
}

long long count_swaps(std::vector<int> s) {
	ll n = s.size();
	vector<ll> neww(n);
	int pnt = 1;
	for (int i = 0; i < n; i++) 
		if (s[i] > 0)
			neww[i] = pnt, pnt += 2;
	pnt = 0;
	for (int i = 0; i < n; i++) 
		if (s[i] < 0)
			neww[i] = pnt, pnt += 2;
	return count_inv(neww);
}

Compilation message (stderr)

shoes.cpp: In function 'll count_inv(std::vector<long long int>)':
shoes.cpp:38:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   38 |  for (int i = 0; i < perm.size(); i++) {
      |                  ~~^~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 0 / 20
• Subtask 3: 20 / 20
• Subtask 4: 15 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 15