Submission #299088

#	Time	Username	Problem	Language	Result	Execution time	Memory
299088		ASDF123	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	2 ms	384 KiB

shoes

#include <bits/stdc++.h>
#include "shoes.h"
//#include "grader.cpp"
using namespace std;

const int N = (int)1e5 + 5;
int tree[N * 4];
int a[N];
bool used[N];
map <int, int> position;

void upd(int pos, int val, int v = 0, int tl = 0, int tr = N) {
  if (tl == tr) {
    tree[v] += val;
    return;
  }
  int mid = (tl + tr) >> 1;
  if (pos <= mid) {
    upd(pos, val, v + v + 1, tl, mid);
  } else {
    upd(pos, val, v + v + 2, mid + 1, tr);
  }
  tree[v] = tree[v + v + 1] + tree[v + v + 2];
}

int get(int l, int r, int v = 0, int tl = 0, int tr = N) {
  if (l > r) {
    return 0;
  }
  if (l <= tl && tr <= r) {
    return tree[v];
  }
  if (l > tr || tl > r) {
    return 0;
  }
  int mid = (tl + tr) >> 1;
  return get(l, r, v + v + 1, tl, mid) + get(l, r, v + v + 2, mid + 1, tr);
}

long long count_swaps(vector<int> a) {
	int n = (int)a.size() / 2;
  for (int i = 0; i < n * 2; i++) {
    cin >> a[i];
    position[a[i]] = i;
  }
  long long ans = 0;
  for (int i = 0; i < n * 2; i++) {
    if (used[abs(a[i])]) {
      continue;
    }
    used[abs(a[i])] = 1;
    int r = position[-a[i]];
    int add = (r + get(r + 1, n * 2 - 1)) - (i + get(i, n * 2 - 1) + 1);
    if (a[i] > 0) {
      add++;
    }
    ans += add;
    upd(r, 1);
  }
  return ans;
}

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