How to return a negative number in python

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Given a list of numbers, write a Python program to print all negative numbers in the given list. 

Example:

Input: list1 = [12, -7, 5, 64, -14]
Output: -7, -14

Input: list2 = [12, 14, -95, 3]
Output: -95

Example #1: Print all negative numbers from the given list using for loop Iterate each element in the list using for loop and check if the number is less than 0. If the condition satisfies, then only print the number. 

Python3

list1 = [11, -21, 0, 45, 66, -93]

for num in list1:

    if num < 0:

    print(num, end=" ")

Output:

-21 -93 

Example #2: Using while loop 

Python3

list1 = [-10, 21, -4, -45, -66, 93]

num = 0

while(num < len(list1)):

    if list1[num] < 0:

        print(list1[num], end=" ")

    num += 1

Output:

-10 -4 -45 -66 

Example #3: Using list comprehension 

Python3

list1 = [-10, -21, -4, 45, -66, 93]

neg_nos = [num for num in list1 if num < 0]

print("Negative numbers in the list: ", *neg_nos)

Output

Negative numbers in the list:  -10 -21 -4 -66

Example #4: Using lambda expressions 

Python3

list1 = [-10, 21, 4, -45, -66, 93, -11]

neg_nos = list(filter(lambda x: (x < 0), list1))

print("Negative numbers in the list: ", *neg_nos)

Output

Negative numbers in the list:  -10 -45 -66 -11

Method: Using enumerate function 

Python3

l=[12, -7, 5, 64, -14]

print([a for j,a in enumerate(l) if a<0])

Method: Using startswith() method

Python3

list1 = [11, -21, 0, 45, 66, -93]

res = []

list2 = list(map(str, list1))

for i in range(0, len(list2)):

    if(list2[i].startswith("-")):

        res.append(str(list1[i]))

res = " ".join(res)

print(res)

Method:  Using numpy.array

Python3

import numpy as np

list1 = [-10, 21, 4, -45, -66, 93, -11]

temp = np.array(list1)

neg_nos = temp[temp <= 0]

print("Negative numbers in the list: ", *neg_nos)

Output:

Negative numbers in the list:  -10 -45 -66 -11