제출 #889809

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
889809		vjudge1	Chorus (JOI23_chorus)	C++17	16 / 100	44 ms	2132 KiB

chorus

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,avx2,fma")
#include <bits/stdc++.h>
 
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define rnd(l, r) uniform_int_distribution<int>(l, r)(rng)
 
using namespace std;

void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);} 
int pow(int a,int b,int m){int ans=1;while(b){if(b&1){ans=(ans*a)%m;}b>>=1;a=(a*a)%m;}return ans;}
int binpow(int a,int b){int ans=1;while(b){if(b&1){ans=(ans*a);}b>>=1;a=(a*a);}return ans;}
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const int N = 3e5 + 5, inf = 1e9, M = 3e4;

int calc(string a, string b){
	int res = 0;
	vector <int> pos;
	for(int i = 0; i < (int)a.size(); i++){
		if(a[i] == 'A'){
			pos.pb(i);
		}
	}
	for(int i  = (int)b.size() - 1; i >= 0; i--){
		if(b[i] == 'A'){
			res += abs(pos.back() - i);
			pos.pop_back();
		}
	}
	return res;
}
	
main(){
	iostream::sync_with_stdio(false);	
    cin.tie(nullptr);
    cout.tie(nullptr);
    int n, k;
    cin >> n >> k;
    n *= 2;
	string s;
	cin >> s;
	set<string> st;
	int ans = inf;
	for(int i = 0; i < ( 1 << n); i++){
		if(__builtin_popcount(i) != n / 2)continue;
		string t = "";
		for(int j = 0; j < n; j++){
			if(i & (1 << j))
				t.pb('B');
			else
				t.pb('A'); 
		}
		string prev = t;
		int r = n - 1, l = n - 1;
		int cnt = 0;
		for(int de = 0; de < k; de++){
			while(r >= 0 && t[r] != 'A'){
				if(t[r] == 'B')
					cnt++;
				r--;
			}
			l = r;
			while(cnt && l >= 0){
				if(t[l] == 'A'){
					cnt--;
					t[l] = '.';
				}
				l--;
			}
		}
		if(l < 0 && cnt == 0){
			st.insert(prev);
			ans = min(ans, calc(s, prev));
			//cout << i << endl;
		}
	}
	cout << ans << endl;
}

/*
 * Before implementing the problem:
	
	Do I understand the problem correctly?
	Which places are tricky? What do I need to remember to implement them correctly?
	Which place is the heaviest by implementation? Can I do it simpler?
	Which place is the slowest? Where do I need to be careful about constant factors and where I can choose slower but simpler implementation?
	----------------------------------
	If not AC:
 
	Did you remember to do everything to handle the tricky places you thought about before?
	Is the solution correct?
	Do I understand the problem correctly?
	----------------------------------
	If you have a test on which the solution gives wrong answer:
 
	Is the solution doing what it was supposed to do?
	Is the problem in the code or in the idea?
*/

컴파일 시 표준 에러 (stderr) 메시지

chorus.cpp:38:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   38 | main(){
      | ^~~~
chorus.cpp: In function 'void fp(std::string)':
chorus.cpp:14:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
chorus.cpp:14:70: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   14 | void fp(string name){freopen((name+".in").c_str(),"r",stdin); freopen((name+".out").c_str(),"w",stdout);}
      |                                                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 0 / 24
• Subtask 3: 0 / 21
• Subtask 4: 0 / 26
• Subtask 5: 0 / 13