C++ 解法, 执行用时: 3ms, 内存消耗: 396KB, 提交时间: 2020-07-16

#include <iostream>
#include <vector>
using namespace std;

struct Node{
    int data;
    int left;
    int right;
    
    Node(int d)
    {
        data = d;
        left = -1;
        right = -1;
    }
    Node(){}
};

const int N = 15000;
int tmp = -99999;
bool isright = true;
Node lib[N];

//中序遍历
void mid(Node node){
    if(node.left != -1)
        mid(lib[node.left]);    //递归左子树
    
    int data = node.data;
    if(data > tmp)
        tmp = data;
    else
    {
        isright = false;
    }
    
    if(node.right != -1)
        mid(lib[node.right]);
}

int main()
{
    int firstdata;
    cin >> firstdata;
    Node firstNode = Node(firstdata);
    lib[1] = firstNode;
    int index =1;
    int t;
    //输入结点
    while (scanf(",%d",&t)){ 
            Node node(t);
            index++;
            lib[index] = node;
    }
        
    int i=1;
    
    //更新左右子树的编号。
    while(i*2 < index){
        lib[i].left = i*2;
        lib[i].right = i*2+1;
        i++;
    }
        
    //中序遍历
    mid(lib[1]);
    
    if(isright){
        cout<<"True"<<endl;
    }else{
        cout<<"False"<<endl;
    }
    
    return 0;
}

C++ 解法, 执行用时: 3ms, 内存消耗: 436KB, 提交时间: 2020-08-18

#include <stdio.h>
#include <vector>
#include <queue>

bool judge(int* data, int len) {
    if (!data || len <= 0) { return true; }
    std::queue<std::pair<int, int> > judges;
    
    judges.push(std::make_pair(-1, -1));
    
    for (int i = 0; i < len; ++i) {
        std::pair<int, int> tmp = judges.front();
        judges.pop();
        if (tmp.first != -1 && tmp.first >= data[i]) { return false; }
        if (tmp.second != -1 && tmp.second <= data[i]) { return false; }
        
        judges.push(std::make_pair(tmp.first, data[i]));
        judges.push(std::make_pair(data[i], tmp.second));
    }
    return true;
}

int main(int argc, char** argv) {
    std::vector<int> data;
    while (true) {
        int tmp = 0;
        if (scanf("%d", &tmp) != 1) {
            break;
        }
        data.push_back(tmp);
        if (getchar() == '\n') {
            break;
        }
    }
    printf("%s\n", judge(&data[0], data.size()) ? "True" : "False");
    
    return 0;
}