Submission #672858

#	Time	Username	Problem	Language	Result	Execution time	Memory
672858		tbzard	Arranging Shoes (IOI19_shoes)	C++14	10 / 100	26 ms	5044 KiB

shoes

#include <bits/stdc++.h>
using namespace std;
int pos[200002], t[200002], cur[200002];
int query(int i){
    int ans = 0;
    for(;i>0;i-=(i&-i)) ans += t[i];
    return ans;
}
void update(int i){
    for(;i<=200000;i+=(i&-i)) t[i]++;
}
long long count_swaps(vector<int> s){
    int n = s.size();
    for(int i=n;i>=1;i--){
        int v = s[i-1];
        if(v < 0) v = -v;
        if(cur[v] == 0) cur[v] = i;
        else pos[i] = cur[v], cur[v] = 0;
    }
    long long ans = 0;
    for(int i=1;i<=n;i++){
        if(pos[i] == 0) continue;
        int cur_pos1 = i + query(2*n) - query(i);
        int cur_pos2 = pos[i] + query(2*n) - query(pos[i]);
        ans += cur_pos2 - cur_pos1 - 1;
        if(s[i-1] > 0) ans++;
        update(pos[i]);
    }
    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