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Geek has several competitive programming books and he wants to place books one on another (like a stack). There are total Q queries of two types.

**Type 1:** This query is represented by **"place x", **where x is an integer represents a number of the book geek wants to place on the top of the stack.

**Type 2:** This query is represented by **"remove". **After** **this query, print a book number which is at the top of the stack (If the stack is empty then print -1) and remove it from the stack.

**Note:** There can be multiple books with the same number.

**Input: **

1. The first line of the input contains a single integer* * **T** denoting the number of test cases. The description of **T** test cases follows.

2. The first line of each test case contains a single integer** Q****.**

3. The next Q lines contain queries

**Output:** For each test case, for each query of type 2, print the top book number of the stack (space separated)

**Constraints:**

1. 1 <= T <= 100

2. 1 <= Q <= 10^{4}

3. 1 <= x <= 10^{9}

**Example:
Input:**

2

5

place 6

place 2

remove

place 3

remove

3

remove

place 5

remove

**Output:**

2 3

-1 5

**Explanation:**

**Test Case 1:** String has an equal number of ones and zeros and at each index(starting from left) the number of occurrences of **0's** is greater than or equals to the number of occurrences **1's**.

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