Description
If the binary tree T and the full binary tree with the same height are numbered, if T and the node with the same number of the full binary tree are in the same position, then the binary tree T is called a complete binary tree. Now judge whether a tree is a complete binary tree based on the connection of the edges.
Input
The input is divided into two parts:
the first part: an integer T, representing the number of test groups.
The second part: there are T groups of data, and the first line of each group has 2 integers n (0 < n < 1024) and r (1 < =r<=n), indicating the number of nodes and the root of the tree, the next n-1 lines have 2 integers a,b (1 <= a, b <= n) in each line, indicating that a node and b node have one The edges are connected, if a is the root node of b, then b is the left child node of a, if b is the root node of a, then a is the right child node of b (the data is guaranteed to be a tree rather than a Forest)
Output
For each set of tests, if the corresponding binary tree is a complete binary tree, output yes, otherwise output no
Sample Input
2
5 1
1 2
3 1
4 2
2 5
5 1
1 2
3 1
4 2
3 5
Sample Output
yes
no
sequential storage
#include<stdio.h>
int chazhao(int x,int y,int n,int a[],int *p);
int panduan (int a [], int n);
void Output(int a[],int n);
intmain()
{
int T;
scanf("%d",&T);
while(T--)
{
int n,g;
scanf("%d%d",&n,&g);
int a[10000]={0};//Initialization
a[1]=g;//The root node enters the array
int x,y;
int p=0,max=1;//max represents the maximum length of the array
for(int i=1;i<n;i++)
{
scanf("%d%d",&x,&y);
a[i];
int flag=chazhao(x,y,max,a,&p);//Find the position in x, y that is the root pointer and bring back the root
if(flag)//Return 1 means x is the root
{
a[p*2]=y;
if(p*2>max)//Update the maximum length
{
max=p*2;
}
}
else
{
a[p*2+1]=x;
if(p*2+1>max)//Update the maximum length
{
max=p*2+1;
}
}
}
//Output(a,max);
int o=panduan(a,max);//Determine whether from a[1] to a[max] is all 0
if(o==0)
printf("no\n");
if(o==1)
printf("yes\n");
}
}
int chazhao(int x,int y,int n,int a[],int *p)
{
for(int i=1;i<=n;i++)
{
if(a[i]==x)
{
*p=i;
return 1;
}
if(a[i]==y)
{
*p=i;
return 0;
}
}
}
int panduan (int a [], int n)
{
for(int i=1;i<=n;i++)
{
if(a[i]==0)
return 0;
}
return 1;
}
void Output(int a[],int n)
{
for(int i=1;i<=n;i++)
{
printf("%d",a[i]);
}
printf("\n");
}