Submission #640190

#	Time	Username	Problem	Language	Result	Execution time	Memory
640190		ymm	Arranging Shoes (IOI19_shoes)	C++17	100 / 100	219 ms	273652 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
#define LoopR(x,l,r) for (ll x = (r)-1; x >= (l); --x)
typedef long long ll;
typedef std::pair<int, int> pii;
typedef std::pair<ll , ll > pll;
using namespace std;

static const int N = 200'010;
static queue<int> l[N], r[N];
static int fen[N];

static void add_fen(int r, int x)
{
	while (r > 0) {
		fen[r] += x;
		r -= r & -r;
	}
}
static void add(int l, int r)
{
	add_fen(r, 1);
	add_fen(l, -1);
}
static int get(int i)
{
	++i;
	int ans = 0;
	while (i < N) {
		ans += fen[i];
		i += i & -i;
	}
	return ans;
}

long long count_swaps(std::vector<int> s) {
	ll ans = 0;
	Loop (i, 0, s.size()) {
		int x = s[i];
		if (x < 0) {
			if (r[-x].size()) {
				ans += i - r[-x].front() - get(r[-x].front());
				add(r[-x].front(), i);
				r[-x].pop();
			} else {
				l[-x].push(i);
			}
		} else {
			if (l[x].size()) {
				ans += i - l[x].front() - get(l[x].front()) - 1;
				add(l[x].front(), i);
				l[x].pop();
			} else {
				r[x].push(i);
			}
		}
	}
	return ans;
}

Compilation message (stderr)

shoes.cpp: In function 'long long int count_swaps(std::vector<int>)':
shoes.cpp:3:40: warning: comparison of integer expressions of different signedness: 'll' {aka 'long long int'} and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    3 | #define Loop(x,l,r) for (ll x = (l); x < (r); ++x)
      |                                        ^
shoes.cpp:39:2: note: in expansion of macro 'Loop'
   39 |  Loop (i, 0, s.size()) {
      |  ^~~~

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