제출 #582063

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
582063		amunduzbaev	Boarding Passes (BOI22_passes)	C++17	25 / 100	2 ms	340 KiB

passes

#include "bits/stdc++.h"
using namespace std;
 
#define ar array
typedef int64_t ll;

const int N = 1e4 + 5;
const int G = 10;
int dp[1 << G], pref[N], suff[N];

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	string s; cin>>s;
	int n = s.size(), g = 0;
	vector<int> used(26);
	for(int i=0;i<n;i++){
		used[s[i] - 'A'] = 1;
	}
	for(int i=1;i<26;i++){
		used[i] += used[i-1];
	}
	for(int i=0;i<n;i++){
		s[i] = used[s[i] - 'A'] + 'A' - 1;
		g = max(g, s[i] - 'A' + 1);
	}
	
	//~ cout<<s<<endl;
	
	memset(dp, 63, sizeof dp);
	dp[0] = 0;
	for(int mask=0;mask < (1 << g);mask++){
		//~ for(int i=0;i<g;i++) cout<<(mask >> i & 1);
		//~ cout<<"\n";
		//~ cout<<dp[mask]<<"\n";
		for(int j=0;j<g;j++){
			if(mask >> j & 1) continue;
			memset(pref, 0, sizeof pref);
			memset(suff, 0, sizeof suff);
			int cnt = 0;
			for(int k=0;k<n;k++){
				if(k) pref[k] += pref[k-1];
				if(s[k] - 'A' == j){
					pref[k] += cnt;
					cnt++;
				}
				if(mask >> (s[k] - 'A') & 1) cnt += 2;
			}
			
			cnt = 0;
			for(int i=n-1;~i;i--){
				if(i + 1 < n) suff[i] += suff[i + 1];
				if(s[i] - 'A' == j){
					suff[i] += cnt;
					cnt++;
				}
				if(mask >> (s[i] - 'A') & 1) cnt += 2;
			}
			
			int res = min(pref[n-1], suff[0]);
			for(int i=1;i<n;i++){
				res = min(res, pref[i-1] + suff[i]);
			}
			
			dp[mask | (1 << j)] = min(dp[mask | (1 << j)], dp[mask] + res);
		}
	}
	
	double res = dp[(1 << g) - 1] / 2.;
	cout<<res<<"\n";
}

• Subtask 1: 0 / 5
• Subtask 2: 25 / 25
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40