제출 #1003923

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1003923		vjudge1	Ekoeko (COCI21_ekoeko)	C++17	110 / 110	29 ms	8392 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
const int maxn = 2e5+5;

int bit[maxn];

void upd(int x){
	for(; x<maxn; x+=x&-x) bit[x]++;
}

int query(int x){
	int rt=0;
	for(; x>0; x-=x&-x) rt+=bit[x];
	return rt;
}

int ord(char c){
	return (int)(c-'a');
}

signed main(){
	int n; cin >> n;
	string s; cin >> s;
	vector<int> mp(26,0), cnt(26,0);
	for(char c : s) cnt[ord(c)]++;

	int cnt1=0, cnt2=0;
	vector<int> arr1, arr2;
	vector<int> trans(2*n,0);
	// cout << endl;
	set<int> pos[26];
	for(int i=0; i<2*n; i++){
		int p = ord(s[i]);

		if(mp[p]<cnt[p]/2){
			mp[p]++;
			cnt1++;
			trans[i]=cnt1;
			pos[p].insert(cnt1);
		}
	}
	for(int i=0; i<2*n; i++) if(!trans[i]){
		int p = ord(s[i]);
		assert(pos[p].size()>0);
		trans[i] = (*pos[p].begin())+n;
		pos[p].erase(pos[p].begin());
	}

	// for(int x : trans) cout << x << " ";
	// cout << endl;

	int ans=0;
	for(int i=0; i<2*n; i++	){
		ans += i-query(trans[i]-1);
		upd(trans[i]);
	}
	cout << ans << '\n';
}

컴파일 시 표준 에러 (stderr) 메시지

Main.cpp: In function 'int main()':
Main.cpp:29:14: warning: unused variable 'cnt2' [-Wunused-variable]
   29 |  int cnt1=0, cnt2=0;
      |              ^~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 20 / 20
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40