Submission #847646

#	Time	Username	Problem	Language	Result	Execution time	Memory
847646		manhlinh1501	Arranging Shoes (IOI19_shoes)	C++17	10 / 100	1 ms	348 KiB

shoes

#include <bits/stdc++.h>
using namespace std;
using i64 = long long;
 
#define lch id << 1
#define rch id << 1 | 1
 
const int N = 2e5 + 5;
 
int bit[N<<1];
int n;
 
void update(int x, int k) {
    for(; x <= n; x += (x & -x))
        bit[x] += k;
}
 
int calc(int x) {
    int res = 0;
 
    for(; x; x -= (x & -x))
        res += bit[x];
 
    return res;
}
 
int get(int x) {
    return calc(x) - calc(x - 1);
}
 
i64 count_swaps(vector<int> a) {
    i64 ans = 0;
    map<int, deque<int>> res;
    n = a.size();
 
    for(int i = 0; i < n; i++) {
        if(res[-a[i]].empty())
            res[a[i]].emplace_back(i);
 
        else {
            int l = res[-a[i]].front() + 1;
            res[-a[i]].pop_front();
            int r = i + 1;
            ans += (r - l) - (get(r) - get(l)) - (a[i] > 0);
            update(l, 1);
            update(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