  # Python | Count true boolean values ​​in a list Examples :

`  Input:  [True, False, True, True, False]  Output:  3  Input:  [False, True, False, True]  Output:  2 `

Method # 1: Using comprehension list

One of the easy ways to count true booleans in a list is to use a list.

 ` # Python3 program for counting true boolean values ​​in a list ``   def count (lst):   return sum ( bool (x) fo r x in lst)   # Driver code lst = [ True , False , True , True , False ] print (count (lst)) `

Exit:

` 3 `

Method # 2: Using `sum()`

` `

` # Python3 program for calculating true logs values ​​in the list   def count (lst):     return sum (lst)   # Driver code lst = [ True , False , True , True , False ] print (count (lst)) `

` ` Exit:

3

A more reliable and transparent way to use sum is shown below.

` `

 ` def ` ` count (lst): `   ` return ` ` sum ` ` (` ` 1 ` ` for ` ` x ` ` in ` ` lst ` ` if ` ` x) `

Method # 3: method `count()`

 ` # Python3 program for counting true boolean values ​​in a list `    ` def ` ` count (lst): `   ` return ` ` lst.count (` ` True ` `) `   ` # Driver code ` ` lst ` ` = ` ` [` ` True ` ` , ` ` False ` `, ` ` True ` `, ` ` True ` `, ` ` False ` `] ` ` print ` ` (count (lst)) `

Exit:

``` 3    Method number 4:  `filter()`` ``       # Python3 program for counting true booleans values ​​in the list        def   count (lst):        return   len   (  list   (  filter   (  None  , lst)))       # Driver code     lst   =   [  True  ,   False  ,   True  ,   True  ,   False  ]    print   (count ( lst)) `` `  Exit:  3

```