Submission #582092

#	Time	Username	Problem	Language	Result	Execution time	Memory
582092		amunduzbaev	Boarding Passes (BOI22_passes)	C++17	25 / 100	52 ms	596 KiB

passes

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

const int G = 15;
int dp[1 << G]; //, pref[N];

signed main(){
	ios::sync_with_stdio(0); cin.tie(0);
	
	string s; cin>>s;
	int n = s.size(), g = 0;
	for(int i=0;i<n;i++){
		g = max(g, (ll)s[i] - 'A' + 1);
	}
	
	
	memset(dp, 127, sizeof dp);
	dp[0] = 0;
	int pref[n + 5] {};
	for(int mask=0;mask < (1 << g);mask++){
		//~ for(int i=0;i<g;i++) cout<<(mask >> i & 1);
		//~ cout<<" "<<dp[mask]<<endl;
		for(int j=0;j<g;j++){
			if(mask >> j & 1) continue;
			memset(pref, 0, sizeof pref);
			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;
			}
			
			int suff = 0, res = pref[n - 1]; cnt = 0;
			for(int i=n-1;~i;i--){
				if(s[i] - 'A' == j){
					suff += cnt, cnt++;
				}
				res = min(res, suff + (i ? pref[i-1] : 0));
				if(mask >> (s[i] - 'A') & 1) cnt += 2;
			}
			//~ for(int l=0;l<g;l++) cout<<((mask >> l & 1) || (l == j));
			//~ cout<<" "<<dp[mask] + res<<endl;
			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