Submission #105233

#	Time	Username	Problem	Language	Result	Execution time	Memory
105233		bert30702	Ancient Books (IOI17_books)	C++17	0 / 100	2 ms	280 KiB

books

#include <bits/stdc++.h>
#include "books.h"
using namespace std;
const int MX = 1e6 + 100;
int G[MX];
long long minimum_walk(vector<int> p, int s) {
	int n = p.size();
	while(p[n - 1] == n - 1 and n - 1 > s) n --;
	long long sum = 0;
	for(int i = 0; i < n; i ++) {
		G[p[i]] = max(G[p[i]], i);
		G[i]    = max(G[i], p[i]);
		sum += abs(i - p[i]);
	}
	for(int i = 0; i < n; i ++) {
		if(p[i] == i and i < s) continue;
		int ptr = i + 1;
		while(ptr <= G[i]) {
			G[i] = max(G[i], G[ptr]);
			ptr ++;
		}
		if(ptr < n) sum += 2;
		i = ptr - 1;
	}
	int mn = MX;
	for(int i = s; i <  n; i ++) if(p[i] != i) mn = min(mn, i - s);
	for(int i = s; i >= 0; i --) if(p[i] != i) mn = min(mn, s - i);
	return sum + mn;
}
//main () {
//	cout << minimum_walk({2, 3, 0, 1}, 0);
//}

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