Question

How to move all negative elements to the beginning of a list in Python

Answer 1

def move_negative_to_beginning(lst):
    size = len(lst)
 
    beginning_index = 0
    for i in range(0, size) :
        if (lst[i] < 0) :
            tmp = lst[i]
            lst[i] = lst[beginning_index]
            lst[beginning_index]= tmp
            
            beginning_index = beginning_index + 1
    
    return lst
 

lst = [-1, 8, -6, 21, -3, 4, -2, 7, 15, -30, -40, 9]

lst = move_negative_to_beginning(lst)

print(lst)



'''
run:

[-1, -6, -3, -2, -30, -40, 21, 7, 15, 8, 4, 9]

'''

 

70+ SQL courses for beginners and professionals