PTA甲級考試真題練習155——1155 Heap Paths

題目

思路

水題

代碼

#include <iostream>
#include <vector>
using namespace std;
vector<int> vec;
vector<int> tmp;
bool isMax = false, isMin = false;
int n;
void DFS(int cur) {
	if (cur != 1) {
		if (vec[cur] > vec[cur / 2])
			isMin = true;
		else
			isMax = true;
	}
	if (2 * cur > n && 2 * cur + 1 > n) {
		for (int i = 0; i < tmp.size(); ++i)
			i == 0 ? cout << vec[tmp[i]] : cout << " " << vec[tmp[i]];
		cout << endl;
		return;
	}
	if (2 * cur + 1 <= n) {
		tmp.emplace_back(2 * cur + 1);
		DFS(2 * cur+1);
		tmp.pop_back();
	}
	if (2 * cur <= n) {
		tmp.emplace_back(2 * cur);
		DFS(2 * cur);
		tmp.pop_back();
	}
}
int main()
{
	cin >> n;
	vec.resize(n + 1);
	for (int i = 1; i <= n; ++i)  cin >> vec[i];
	tmp.emplace_back(1);
	DFS(1);
	tmp.pop_back();
	if (isMax && isMin)
		cout << "Not Heap";
	else if (isMax && !isMin)
		cout << "Max Heap";
	else
		cout << "Min Heap";
	return 0;
}