Given a list of numbers, write a Python program to print all positive numbers in given list.
Example:
Input: list1 = [12, -7, 5, 64, -14] Output: 12, 5, 64 Input: list2 = [12, 14, -95, 3] Output: [12, 14, 3]
Example #1: Print all positive numbers from given list using for loop Iterate each element in the list using for loop and check if number is greater than or equal to 0. If the condition satisfies, then only print the number.
Python3
# Python program to print positive Numbers in a List # list of numbers list1 = [ 11 , - 21 , 0 , 45 , 66 , - 93 ] # iterating each number in list for num in list1: # checking condition if num & gt = 0 : print (num, end = & quot & quot ) |
Output:
11 0 45 66
Time Complexity: O(n)
Auxiliary Space: O(1)
Example #2: Using while loop
Python3
# Python program to print positive Numbers in a List # list of numbers list1 = [ - 10 , 21 , - 4 , - 45 , - 66 , 93 ] num = 0 # using while loop while (num < len (list1)): # checking condition if list1[num] > = 0 : print (list1[num], end = " ") # increment num num + = 1 |
Output:
21 93
Time complexity : O(n)
Space complexity : O(1)
Example #3: Using list comprehension
Python3
# Python program to print Positive Numbers in a List # list of numbers list1 = [ - 10 , - 21 , - 4 , 45 , - 66 , 93 ] # using list comprehension pos_nos = [num for num in list1 if num > = 0 ] print ("Positive numbers in the list : ", * pos_nos) |
Output:
Positive numbers in the list: 45 93
Time complexity : O(n), where n is length of list.
Auxiliary Space : O(1)
Example #4: Using lambda expressions
Python3
# Python program to print positive Numbers in a List # list of numbers list1 = [ - 10 , 21 , 4 , - 45 , - 66 , 93 , - 11 ] # we can also print positive no's using lambda exp. pos_nos = list ( filter ( lambda x: (x > = 0 ), list1)) print ("Positive numbers in the list : ", * pos_nos) |
Output:
Positive numbers in the list: 21, 4, 93
Time complexity of the program is O(n), where n is the number of elements in the list.
Space complexity of the program is also O(n), where n is the number of elements in the list.
Method: Using enumerate function
Python3
l = [ 12 , - 7 , 5 , 64 , - 14 ] print ([a for j,a in enumerate (l) if a> = 0 ]) |
[12, 5, 64]
Method:Using startswith() method
Python3
# Python program to print positive numbers in a List # list of numbers list1 = [ 11 , - 21 , 0 , 45 , 66 , - 93 ] res = [] list2 = list ( map ( str ,list1)) for i in range ( 0 , len (list2)): if ( not list2[i].startswith( "-" ) and list2[i] ! = "0" ): res.append( str (list1[i])) res = " " .join(res) print (res) |
11 45 66
Auxiliary Space: O(n)
Time complexity :O(n)
Method: Using Numpy Array:
Python
# Python program to print Positive Numbers in a List import numpy as np # list of numbers list1 = np.array([ - 10 , - 21 , - 4 , 45 , - 66 , 93 ]) # using numpy Array pos_nos = list1[list1 > = 0 ]; print ( "Positive numbers in the list: " , * pos_nos) |
Output:
Positive numbers in the list: 45 93
The time complexity of this program is O(n), where n is the number of elements in the input list.
The space complexity of this program is also O(n), where n is the number of elements in the input list.
Method: Using recursion
Python3
#Function to print even numbers in a list def PrintEven(itr,list1): if itr = = len (list1): #Base Condition return if list1[itr]> = 0 : print (list1[itr],end = " " ) PrintEven(itr + 1 ,list1) #Recursive Function Call return list1 = [ - 5 , 7 , - 19 , 10 , 9 ] #list of numbers PrintEven( 0 ,list1) #Function Call #This code is contributed by vinay pinjala |
7 10 9
Time complexity:
The time complexity of this function is O(N), where N is the length of the list list1.
Space complexity:
The space complexity of this function is O(N), where N is the length of the list list1.
Method : Using operator.ge()
Python3
# Python program to print positive Numbers in a List # list of numbers list1 = [ - 10 , 21 , 4 , - 45 , - 66 , 93 , - 11 ] import operator pos_nos = [] for i in list1: if operator.ge(i, 0 ): pos_nos.append(i) print ( "Positive numbers in the list: " , pos_nos) |
Positive numbers in the list: [21, 4, 93]
Time Complexity : O(N)
Auxiliary Space : O(N)