Code is for counting the no. Of elements ocuring once or more. I wan to ask why after the first element its counting wrong??Help

Question

lst=eval(input('Enter a list:'))
length=len(lst)
uniq=[]
dupl=[]
count=0
i=0
while i<length:
element=lst[i]#the first element at first
count=1#counts itself
if element not in uniq and element not in dupl:#will be true for the first time
i=+1
for j in range(i,length):#starts from second element at first
if element==lst[j]:
count+=1
else:
print('Element',element,'Frequency',count)
if count==1:
uniq.append(element)
else:
dupl.append(element)
else:
i+=1
print('Original list',lst)
print('Unique elements list',uniq)
print('Duplicate elements list',dupl)

Answer 1

Yogesh , if you just wanted to get a kind of counter for the elements of an iterable like list of string, it is recommended to rewrite the code. I would recommend you to start with a for loop version: ( there are several ways to do this task in less code or more elegant, but try to start with a for loop version)

- use a for loop to iterate through the input list, but to get only unique values you have to convert it to a set before
- use each value you get in the loop to count (using count() function) how often it appears in the input iterable
- use the number of counts and the value from the loop to generate the output with print.

It may sounds s big of complicated, but it is not. Here are thd first 2 lines of code - try to do do the rest by yourself:

inp = [1,3,6,9,0,4,9,2,1,4,9,0,1,2]

for i in set(inp):
...
# it needs 3 or 4 lines more to get this output:

0 occurs 2 x times
1 occurs 3 x times
2 occurs 2 x times
3 occurs 1 x times
4 occurs 2 x times
6 occurs 1 x times
9 occurs 3 x times

Answer 2

Yogesh

U r repeatedly increasing the value of "i" so it was the bug..

https://code.sololearn.com/c52hDpHgI75v/?ref=app

Check python dictionary....
https://www.sololearn.com/learn/Python/2450/?ref=app

Example code to count duplicate elements of the list

list=[2,2,2,4,5,6,8,8,6,5,4]
dictionary={}
for i in list:
if i in dictionary:
dictionary[i]+=1
else:
dictionary[i]=1
print(dictionary)

Answer 3

Search "list comprehension with condition" and the "set" container, this task can be done with two lines of code.