String Rotation

Question

I have solved a previous year question of 2018 codevita (link) in Python.

Problem Description:

Rotate a given String in the specified direction by specified magnitude.
After each rotation make a note of the first character of the rotated String, After all rotation are performed the accumulated first character as noted previously will form another string, say FIRSTCHARSTRING.
Check If FIRSTCHARSTRING is an Anagram of any substring of the Original string.
If yes print "YES" otherwise "NO".

Here is the code:

from collections import Counter

def lrotate(input,d): 
    Lfirst = input[0 : d] 
    Lsecond = input[d :] 

    return (Lsecond + Lfirst) 

def rrotate(input,d):
    Rfirst = input[0 : len(input)-d] 
    Rsecond = input[len(input)-d : ] 

    return (Rsecond + Rfirst)


s=input()
n=int(input())
c='FIRSTCHARSTRING'
l=[]
for _ in range(n):
    w,v=input().split()
    v=int(v)
    if w == 'L':
        p=lrotate(c,v)
    if w == 'R':
        p=rrotate(c,v)
    l.append(p[0])

if Counter(l) == Counter(s) :
    print("Yes")
else:
    print("No")

What can I do to optimize my code?

Answer 1

You can use python deque function to rotate string.

word = 'FIRSTCHARSTRING'
commands = [
  ('L', 2),
  ('R', 3),
  ('L', 1),
]

from collections import deque

q = deque(word)

for direction, magnitude in commands:
  if direction == 'L':
    q.rotate(-magnitude)
  else:
    q.rotate(magnitude)

if ''.join(q) == word:
    print('Yes')
else:
    print('No')