Submission #152524

#	Time	Username	Problem	Language	Result	Execution time	Memory
152524		groeneprof	Ancient Books (IOI17_books)	C++14	100 / 100	171 ms	15048 KiB

books

#include <bits/stdc++.h>
#include "books.h"
using namespace std;


long long minimum_walk(vector<int> p, int s) {
	int i = s; 
	int j = s-1;//incl-incl
	int mi = s,  ma=s;
	int n = p.size();
	long long cnt  = 0, curl = 0, curr = 0;
	int b = 0, e = n;
	for(int k = 0; k<s&&p[k]==k; k++) b = k+1;
	for(int k = n-1; k>s&&p[k]==k; k--) e = k;	
	

	while(i>b||j<e-1){
		bool bol = false;
		while(mi < i){
			bol = true;
			i--;
			if(p[i]>s){
				cnt += curl;
				curl = 0;
				curr = 0;
			}
			mi = min(mi, p[i]);
			ma = max(ma, p[i]);
		}
		while(j<ma){
			bol = true;
			j++;
			if(p[j]<s){
				cnt+=curr;
				curl = 0;
				curr = 0;
			}
			mi = min(mi, p[j]);
			ma = max(ma, p[j]);
			
		}
		if(!bol){
			//cur+=2;
			//cout<<mi<<" "<<ma<<endl;
			if(mi>b){mi--;curl+=2;}
			if(ma<e-1){ma++;curr+=2;}
		}

	}
	//cnt+=<
	//cout<<cnt<<endl;
	cnt+=curl+curr;
	for(int ii = 0; ii<n; ii++){
		cnt += abs(ii - p[ii]);
	}

	return cnt;
}

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 28 / 28
• Subtask 4: 20 / 20
• Subtask 5: 30 / 30