Submission #71215

#	Time	Username	Problem	Language	Result	Execution time	Memory
71215		Kmcode	Ancient Books (IOI17_books)	C++14	50 / 100	256 ms	16336 KiB

books

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


int im1[1000002];
int im2[1000002];

long long minimum_walk(std::vector<int> p, int s) {
	for(int i=0;i<p.size();i++){
		if(i<=p[i]){
			im1[i]++;
			im1[p[i]]--;
		}
		else{
			im2[p[i]]++;
			im2[i]--;
		}
	}
	for(int i=1;i<p.size();i++){
		im1[i]+=im1[i-1];
		im2[i]+=im2[i-1];
	}
	int ava=0;
	long long int turn=0;
	for(int i=p.size()-1;i>=s;i--){
		if(im1[i]||im2[i]){
			ava=1;
		}
		int need=max(im1[i],im2[i]);
		need*=2;
		need=max(need,ava*2);
		turn+=need;
	}
	ava=0;
	for(int i=0;i<s;i++){
		if(im1[i]||im2[i]){
			ava=1;
		}
		int need=max(im1[i],im2[i]);
		need*=2;
		need=max(need,ava*2);
		turn+=need;
	}
	return turn;
}

Compilation message (stderr)

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:10:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=0;i<p.size();i++){
              ~^~~~~~~~~
books.cpp:20:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i=1;i<p.size();i++){
              ~^~~~~~~~~

• Subtask 1: 12 / 12
• Subtask 2: 10 / 10
• Subtask 3: 28 / 28
• Subtask 4: 0 / 20
• Subtask 5: 0 / 30