Submission #529861

#	Time	Username	Problem	Language	Result	Execution time	Memory
529861		buidangnguyen05	Arranging Shoes (IOI19_shoes)	C++14	100 / 100	384 ms	148876 KiB

shoes

/* input

*/

#include<bits/stdc++.h>
using namespace std;

typedef long long ll;
const int N = 2e5 + 10;
int nxt[N], bit[N], n; bool solved[N];
map<int, queue<int>> q;

void up(int x, int val) {
	while (x) {
		bit[x] += val;
		x -= x & (-x);
	}
}

int get(int x) {
	int ret = 0;
	while (x <= n) {
		ret += bit[x];
		x += x & (-x);
	}
	return ret;
}

ll count_swaps(vector<int> v) {
	n = v.size();
	v.insert(v.begin(), 0);
	for (int i = 1; i <= n; ++i) {
		if (q[-v[i]].size()) {
			int x = q[-v[i]].front(); q[-v[i]].pop();
			nxt[x] = i;
		}
		else q[v[i]].push(i);
	}

	ll ret = 0;
	for (int i = 1; i <= n; ++i) if (!solved[i]) {
		int L = i + get(i), R = nxt[i] + get(nxt[i]);
		//cout << i << " " << nxt[i] << " " << L << " " << R << "\n";
		ret += R - L - 1 + (v[i] > 0);
		up(nxt[i], 1); solved[nxt[i]] = 1;
	}

	return ret;
}

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