Trick #1
Reversing a string in Python
>>> a = "codementor">>> print "Reverse is",a[::-1]
Reverse is rotnemedoc
Trick #2
Transposing a Matrix
>>> mat = [[1, 2, 3], [4, 5, 6]]
>>> zip(*mat)
[(1, 4), (2, 5), (3, 6)]
Trick #3
a = [1,2,3]
Store all three values of the list in 3 new variables
>>> a = [1, 2, 3]
>>> x, y, z = a
>>> x
1
>>> y
2
>>> z
3
Trick #4
a = [“Code”, “mentor”, “Python”, “Developer”]
Create a single string from all the elements in list above.</h5>
```python
print “ “.join(a)
Code mentor Python Developer
```
Trick #5
list1 = [‘a’, ‘b’, ‘c’, ‘d’]
list2 = [‘p’, ‘q’, ‘r’, ‘s’]
Write a Python code to print
ap
bq
cr
ds
>>> for x, y in zip(list1,list2):
... print x, y
...
a p
b q
c r
d s
Trick #6
Swap two numbers with one line of code.
>>> a=7
>>> b=5
>>> b, a =a, b
>>> a
5
>>> b
7
Trick #7
print “codecodecodecode mentormentormentormentormentor” without using loops
>>> print "code"*4+' '+"mentor"*5
codecodecodecode mentormentormentormentormentor
Trick #8
a = [[1, 2], [3, 4], [5, 6]]
Convert it to a single list without using any loops.
Output:- [1, 2, 3, 4, 5, 6]
>>> import itertools
>>> list(itertools.chain.from_iterable(a))
[1, 2, 3, 4, 5, 6]
Trick #9
Checking if two words are anagrams
def is_anagram(word1, word2):
"""Checks whether the words are anagrams.
word1: string
word2: string
returns: boolean
"""Complete the above method to find if two words are anagrams.python
from collections import Counter
def is_anagram(str1, str2):
return Counter(str1) == Counter(str2)
>>> is_anagram('abcd','dbca')
True
>>> is_anagram('abcd','dbaa')
False
Trick #10.
Take a string input.
For example “1 2 3 4” and return [1, 2, 3, 4]
Remember list being returned has integers in it.
Don’t use more than one line of code.
>>> result = map(lambda x:int(x) ,raw_input().split())
1 2 3 4
>>> result
[1, 2, 3, 4]