1110. Complete Binary Tree (25)

传送门://https://www.patest.cn/contests/pat-a-practise/1110
312比赛的时候 由于读入方式有错  看到2个 - - 就用char来接收 导致3个测试点过不去,后来改正确后顺利AC
AC 代码
#include <iostream>
#include <vector>
#include <map>
#include <unordered_map>
#include <set>
#include <algorithm>
#include <string>
#include <string.h>
#include <cstdio>
#include <queue>
#include <stack>
#include <limits>
using namespace std;
struct Node{
int no;
Node *parent,*left,*right;
Node():parent(NULL),left(NULL),right(NULL){};
};
int main()
{
int n;
scanf("%d",&n);
vector<Node *>tree;
string a,b;
for(int i=0;i<n;++i)
tree.push_back(new Node());
for(int i=0;i<n;++i){
cin>>a>>b;
tree[i]->no = i;
if(a[0]!='-'){
int x;
sscanf(a.c_str(),"%d",&x);
tree[x]->parent = tree[i];
tree[i]->left = tree[x];
}
if(b[0]!='-'){
int x;
sscanf(b.c_str(),"%d",&x);
tree[x]->parent = tree[i];
tree[i]->right = tree[x];
}
}
Node *root = NULL;
for(int i=0;i<n;++i){
if(tree[i]->parent == NULL){
root = tree[i];
break;
}
}
queue<Node *>q;
vector<int>ans;
if(root){
q.push(root);
ans.push_back(root->no);
}
while(!q.empty()){
Node * p = q.front();
q.pop();
if(p->left){
q.push(p->left);
ans.push_back(p->left->no);
}else
break;
if(p->right){
q.push(p->right);
ans.push_back(p->right->no);
}else
break;
}
if(ans.size()==n){
printf("YES %d\n",ans.back());
}else
printf("NO %d\n",ans[0]);
return 0;
}