Problem A: Complete binary tree

## Problem A: Complete binary tree

Time Limit: 1 Sec  Memory Limit: 128 MB
Submit: 3068  Solved: 575
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## Description

Lanran has a binary tree with $$n$$ nodes, she does not know whether this tree is a complete binary tree or not. She turns to you for help. We guarantee that the input is a binary tree.

## Input

The first line will be an integer $$T$$, which is the number of the test cases.$$(1 \le T \le 14)$$ For each test case, the first line will be an integer $$n$$.$$(1\le n\le 150000)$$Then followed by $$n$$ lines, each line will be two integers $$x$$ and $$y$$, the i-th line means the left child of node i is $$x$$, the right child of node i is $$y$$. If node i has no left child, then $$x$$ will be 0. If node i has no right child, then $$y$$ will be 0.

## Output

For each test output Yes or No in one line.

## Sample Input

1
5
2 3
4 0
5 0
0 0
0 0

## Sample Output

No

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