Submission #980122

#	Time	Username	Problem	Language	Result	Execution time	Memory
980122		ShaShi	Arranging Shoes (IOI19_shoes)	C++17	0 / 100	774 ms	1048576 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
#define F first
#define S seond
#define all(x) x.begin(), x.end()
#define pb push_back
#define mp make_pair
#define pii pair<int, int>


using namespace std;
typedef long long ll;

const int MAXN = (int)1e6 + 7;
const int MOD = 998244353;
const int INF = (int)1e9 + 7;



int n, m, t, tmp, tmp2, tmp3, u, v, w, ans;
deque<int> vec[2][MAXN];

/* BIT */
int fen[MAXN];

inline void upd(int x, int y) {
	for (x++; x<MAXN; x+=x&-x) fen[x] += y;
}


inline int get(int x) {
	int res = 0;
	for (x++; x>0; x-=x&-x) res += fen[x];
	return res;
}

/* BIT */

ll count_swaps(vector<int> s) {
	n = s.size()/2;
	ans = 0;

	for (int i=0; i<2*n; i++) {
		upd(i, 1);

		if (s[i] < 0) vec[0][0-s[i]].pb(i);
		else vec[1][s[i]].pb(i);
	}

	for (int j=0; j<2*n; j++) {
		if (get(j)-get(j-1) == 0) continue;

		if (s[j] < 0) {
			tmp2 = vec[1][0-s[j]].front(); vec[1][0-s[j]].pop_front(); vec[0][0-s[j]].pop_front();

			// cout << "@" << s[j] << " " << s[tmp2] << endl;
			// cout << "!" << get(tmp2-1) << " " << get(j) << endl;

			ans += get(tmp2-1)-get(j);
			upd(tmp2, -1);
		} else {
			tmp2 = vec[0][s[j]].front(); vec[1][s[j]].pop_front(); vec[0][s[j]].pop_front();

			// cout << "@" << s[j] << " " << s[tmp2] << endl;
			// cout << "!" << get(tmp2) << " " << get(j) << endl;

			ans += get(tmp2)-get(j);
			upd(tmp2, -1);
		}

		upd(j, -1);
	}

	return ans;
}

// int main() {
// 	int n;
// 	assert(1 == scanf("%d", &n));
// 	vector<int> S(2 * n);
// 	for (int i = 0; i < 2 * n; i++)
// 		assert(1 == scanf("%d", &S[i]));
// 	fclose(stdin);

// 	long long result = count_swaps(S);

// 	printf("%lld\n", result);
// 	fclose(stdout);
// 	return 0;
// }

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