In this Collections.deque() problem we need to develop a python program that can read integer and space separated methods on the next line. and we need to print the space-separated elements on the output screen.

## Problem solution in Python 2 programming.

```# Enter your code here. Read input from STDIN. Print output to STDOUT
from collections import deque
d=deque()
N=int(raw_input())
for i in range(N):
A=list(raw_input().split())
if A=='append':
d.append(int(A))
elif A=='appendleft':
d.appendleft(int(A))
elif A=='pop':
d.pop()
elif A=='popleft':
d.popleft()
for i in d:
print i,```

## Problem solution in Python 3 programming.

```# Enter your code here. Read input from STDIN. Print output to STDOUT
from collections import deque
d = deque()
for _ in range(int(input())):
inp = input().split()
getattr(d, inp)(*[inp] if len(inp) > 1 else [])
print(*[item for item in d])```

### Problem solution in pypy programming.

```# Enter your code here. Read input from STDIN. Print output to STDOUT
from collections import deque
d = deque()
for i in range(input()):
eval('d.{0}({1})'.format(*raw_input().split()+['']))
print ' '.join(map(str,d)) ```

### Problem solution in pypy3 programming.

```# https://www.hackerrank.com/challenges/py-collections-deque?h_r=next-challenge&h_v=zen

from collections import deque

d = deque()
for i in range(int(input())):

operation, *number = input().split()
if number:
num1 = int(number)
if operation == 'append':
d.append(num1)
elif operation == 'appendleft':
d.appendleft(num1)
elif operation == 'pop':
d.pop()
elif operation == 'popleft':
d.popleft()

for i in range(len(d)):
print(d.popleft(), end = ' ')```