1155 Heap Paths

In computer science, a heap is a specialized tree-based data structure that satisfies the heap property: if P is a parent node of C, then the key (the value) of P is either greater than or equal to (in a max heap) or less than or equal to (in a min heap) the key of C. A common implementation of a heap is the binary heap, in which the tree is a complete binary tree. (Quoted from Wikipedia at https://en.wikipedia.org/wiki/Heap_(data_structure))

One thing for sure is that all the keys along any path from the root to a leaf in a max/min heap must be in non-increasing/non-decreasing order.

Your job is to check every path in a given complete binary tree, in order to tell if it is a heap or not.

Input Specification:
Each input file contains one test case. For each case, the first line gives a positive integer N (1<N≤1,000), the number of keys in the tree. Then the next line contains N distinct integer keys (all in the range of int), which gives the level order traversal sequence of a complete binary tree.

Output Specification:
For each given tree, first print all the paths from the root to the leaves. Each path occupies a line, with all the numbers separated by a space, and no extra space at the beginning or the end of the line. The paths must be printed in the following order: for each node in the tree, all the paths in its right subtree must be printed before those in its left subtree.

Finally print in a line Max Heap if it is a max heap, or Min Heap for a min heap, or Not Heap if it is not a heap at all.

Sample Input 1:
8
98 72 86 60 65 12 23 50
Sample Output 1:
98 86 23
98 86 12
98 72 65
98 72 60 50
Max Heap
Sample Input 2:
8
8 38 25 58 52 82 70 60
Sample Output 2:
8 25 70
8 25 82
8 38 52
8 38 58 60
Min Heap
Sample Input 3:
8
10 28 15 12 34 9 8 56
Sample Output 3:
10 15 8
10 15 9
10 28 34
10 28 12 56
Not Heap

#include <bits/stdc++.h>
using na
mespace std;
vector<int> v, vx;
int n, res;
void MaxHeap(int i){
    if(i <= n){
        if((2 * i + 1 <= n && v[2 * i + 1] > v[i]) || (2 * i <= n && v[2 * i] > v[i])) res = 0;
        if((2 * i > n)) vx.push_back(i);
        MaxHeap(2 * i + 1);
        MaxHeap(2 * i);
    }
}
void MinHeap(int i){
    if(i <= n){
        if((2 * i + 1 <= n && v[2 * i + 1] < v[i]) || (2 * i <= n && v[2 * i] < v[i])) res = 0;
        if((2 * i > n)) vx.push_back(i);
        MinHeap(2 * i + 1);
        MinHeap(2 * i);
    }
}
void prt(vector<int> &vx){
    for(int i: vx){
        stack<int> stk;
        while(i >= 1){
            stk.push(v[i]);
            i /= 2;
        }
        while(!stk.empty()){
            stk.size() == 1 ? printf("%d\n", stk.top()) : printf("%d ", stk.top());
            stk.pop();
        }
    }
}
int main()
{
    cin >> n;
    v.resize(n + 1);
    for(int i = 1; i <= n; ++i){
        cin >> v[i];
    }
    res = 1;
    if(v[1] > v[2]){
        MaxHeap(1);
        prt(vx);
        res ? printf("Max Heap\n") : printf("Not Heap\n");
    }else{
        MinHeap(1);
        prt(vx);
        res ? printf("Min Heap\n") : printf("Not Heap\n");
    }
    return 0;
}