Submission #428631

#	Time	Username	Problem	Language	Result	Execution time	Memory
428631		shenxy	Cheerleaders (info1cup20_cheerleaders)	C++11	41 / 100	846 ms	140244 KiB

cheerleaders

#include <cstdio>
#include <algorithm>
#include <vector>
using namespace std;
int inv[17], niv[17];
struct seg {
	int s, v;
	seg *l, *r;
	seg(int _s) {
		s = _s, v = 0;
		if (s) {
			l = new seg(s - 1);
			r = new seg(s - 1);
		}
	}
	void update(int i) {
		if (s) {
			if (i < (1 << (s - 1))) l -> update(i), inv[s - 1] += r -> v;
			else r -> update(i - (1 << (s - 1))), niv[s - 1] += l -> v;
			v = l -> v + r -> v;
		} else ++v;
	}
} *root;
int main() {
	int N, h;
	scanf("%d", &N);
	if (N == 0) {
		printf("0\n11");
		return 0;
	}
	int a[1 << N], ans[N];
	vector<int> res[N];
	fill_n(ans, N, 0);
	for (int i = 0; i < (1 << N); ++i) scanf("%d", &h), a[h] = i;
	for (int i = 0; i < N; ++i) {
		for (int j = 0; j < i; ++j) res[i].push_back(2);
		root = new seg(N);
		fill_n(inv, N, 0);
		fill_n(niv, N, 0);
		for (int j = 0; j < (1 << N); ++j) root -> update(a[j]);
		for (int j = N - 1; j >= 0; --j) {
			if (inv[j] > niv[j]) res[i].push_back(1), ans[i] += niv[j];
			else ans[i] += inv[j];
			res[i].push_back(2);
		}
		for (int j = 0; j < (1 << N); ++j) a[j] = (a[j] >> 1) + ((1 & a[j]) << (N - 1));
	}
	printf("%d\n", *min_element(ans, ans + N));
	for (int i: res[min_element(ans, ans + N) - ans]) printf("%d", i);
	return 0;
}

Compilation message (stderr)

cheerleaders.cpp: In function 'int main()':
cheerleaders.cpp:26:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |  scanf("%d", &N);
      |  ~~~~~^~~~~~~~~~
cheerleaders.cpp:34:42: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |  for (int i = 0; i < (1 << N); ++i) scanf("%d", &h), a[h] = i;
      |                                     ~~~~~^~~~~~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 5 / 10
• Subtask 3: 20 / 25
• Subtask 4: 0 / 21
• Subtask 5: 0 / 28