Submission #528262

#	Time	Username	Problem	Language	Result	Execution time	Memory
528262		happypotato	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	1 ms	300 KiB

shoes

#include "shoes.h"
#include <bits/stdc++.h>
using namespace std;
const int mxN = 2e5 + 1;
int seg[4 * mxN];
int n;
void update(int tar, int l = 0, int r = n * 4 - 1, int idx = 1) {
    if (l == r) {
        seg[idx] ^= 1;
        return;
    }
    int mid = (l + r) >> 1;
    if (tar <= mid) update(tar, l, mid, (idx << 1));
    else update(tar, mid + 1, r, (idx << 1) + 1);
    seg[idx] = seg[(idx << 1)] + seg[(idx << 1) + 1];
    return;
}
int query(int tarl, int tarr, int l = 0, int r = n * 4 - 1, int idx = 1) {
    if (tarl <= l && r <= tarr) return seg[idx];
    else if (tarr < l || r < tarl) return 0;
    int mid = (l + r) >> 1;
    return query(tarl, min(tarr, mid), l, mid, (idx << 1)) + query(max(tarl, mid + 1), tarr, mid + 1, r, (idx << 1) + 1);
}
long long count_swaps(vector<int> s) {
    n = s.size() / 2;
    queue<int> q[n + 1];
    for (int i = 0; i < n * 2; i++) {
        if (s[i] < 0) q[-s[i]].push(i * 2 + 1);
    }
    for (int i = 0; i < n * 2; i++) update(i * 2 + 1);
    long long ans = 0;
    for (int i = 0; i < n * 2; i++) {
        if (s[i] < 0) continue;
        int tar = q[s[i]].front(); q[s[i]].pop();
        if (i * 2 + 1 < tar) ans += query(i * 2 + 1, tar - 1);
        else ans += query(tar + 1, i * 2);
        update(tar);
        update(i * 2);
    }
    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