Queue Reversal

Author: anantkaushik

Python/GeeksforGeeks/queue-reversal.py

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+"""
+Problem Link: https://practice.geeksforgeeks.org/problems/queue-reversal/1
+
+Given a Queue Q containing N elements. The task is to reverse the Queue. 
+Your task is to complete the function rev(), that reverses the N elements of the queue.
+
+Input Format: 
+The first line of input contains an integer T denoting the Test cases. Then T test cases follow. 
+The first line contains N which is the number of elements which will be reversed. 
+Second line contains N space seperated elements.
+
+Output Format:
+For each testcase, in a new line, print the reversed queue.
+
+Your Task:
+This is a function problem. You only need to complete the function rev that takes a queue as 
+parameter and returns the reversed queue. The printing is done automatically by the driver code.
+
+Constraints:
+1 ≤ T ≤ 100
+1 ≤ N ≤ 105
+1 ≤ elements of Queue ≤ 105
+
+Example:
+Input : 
+2
+6
+4 3 1 10 2 6
+4
+4 3 2 1 
+
+Output : 
+6 2 10 1 3 4
+1 2 3 4
+"""
+if __name__=='__main__':
+    t=int(input())
+    for i in range(t):
+        n=int(input())
+        q=list(map(int,input().split()))
+        reverseQueue(q)
+
+''' This is a function problem.You only need to complete the function given below '''
+#User function Template for python3
+def reverseQueue(q):
+    #add code here
+    stack = []
+    while q:
+        stack.append(q.pop(0))
+    while stack:
+        q.append(stack.pop())
+    print(*q)