Sometimes in a given Python list we may be interested only in the first digit of each element in the list. In this article we will check if the first digit of all the elements in a list are same or not.
With set and map
Set in Python does not allow any duplicate values in it. So we take the first digit of every element and put it in a set. If all the digits are same then the length of the set will be only 1 has no duplicates allowed.
Example
Alist = [63,652,611,60]
# Given list
print("Given list : ",Alist)
# Using set and map
if len(set(x[0] for x in map(str, Alist))) == 1:
print("All elements have same first digit")
else:
print("Not all elements ,have same first digit")Output
Running the above code gives us the following result −
Given list : [63, 652, 611, 60] All elements have same first digit
With all
In this approach we take the first digit of the first element and compare it with the first digit of all the elements. If all of them are equal, then we say all the elements have same first digit.
Example
Alist = [63,652,611,70]
# Given list
print("Given list : ",Alist)
# Using set and map
if all(str(i)[0] == str(Alist[0])[0] for i in Alist):
print("All elements have same first digit")
else:
print("Not all elements ,have same first digit")Output
Running the above code gives us the following result −
Given list : [63, 652, 611, 70] Not all elements, have same first digit