Submission #559689

#	Time	Username	Problem	Language	Result	Execution time	Memory
559689		nonsensenonsense1	Ancient Books (IOI17_books)	C++17	50 / 100	113 ms	15840 KiB

books

#include "books.h"
#include <cassert>
#include <cstdlib>

const int N = 1000000;
int n;
bool u[N];

long long minimum_walk(std::vector<int> p, int s) {
	long long ans = 0;
	n = (int)p.size();
	int mx = -1, come = ~(1 << 31);
	for (int i = 0; i < n; ++i) if (p[i] != i) {
		come = std::min(come, abs(i - s));
		if (!u[i]) {
			if (i > mx && mx != -1) {
				if (s > mx && s < i) come = 0;
				ans += i - mx << 1;
			}
			int cur = i;
			do {
				ans += abs(cur - p[cur]);
				mx = std::max(mx, cur);
				u[cur] = 1;
				cur = p[cur];
			} while (cur != i);
		}
	}
	if (mx == -1) return 0;
	return ans + come * 2;
}

Compilation message (stderr)

books.cpp: In function 'long long int minimum_walk(std::vector<int>, int)':
books.cpp:18:14: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   18 |     ans += i - mx << 1;
      |            ~~^~~~

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