Merge Value In The Same Array (Python)?

Question

I have the shortcode in Python like this:

a = [1, 2, 3]

b = a

b[0] = 100

print(a)

But I am getting the below result:

Output: [100, 2, 3]

How do I fix it?

Answer 1

In your example, both 'b' and 'a' are referring to an object. You should make a separate copy if you wish to change each of them independently. To solve it you have different ways: 

Option 1:

def Cloning(li1): 

    li_copy = li1[:] 

    return li_copy 

a = [1, 2, 3,] 

b = Cloning(a) 

b[0] = 100

print("Original List:", a) 

print("After Cloning:", b) 

2:

# Using the in-built function extend() 

def Cloning(li1): 

    li_copy = [] 

    li_copy.extend(li1) 

    return li_copy 

# Driver Code 

a = [1, 2, 3] 

b = Cloning(li1) 

b[0] = 100

print("Original List:", a) 

print("After Cloning:", b)

Option 3:

# Using the in-built function list() 

def Cloning(li1): 

    li_copy = list(li1) 

    return li_copy 

# Driver Code 

a = [1, 2, 3] 

b = Cloning(li1) 

b[0] = 100

print("Original List:", a) 

print("After Cloning:", b)

Option 4:

# Using list comprehension 

def Cloning(li1): 

    li_copy = [i for i in li1] 

    return li_copy 

  

# Driver Code 

    a = [1, 2, 3] 

    b = Cloning(li1) 

    b[0] = 100

    

    print("Original List:", a) 

    print("After Cloning:", b)

Option 5:

# Using append() 

def Cloning(li1): 

    li_copy =[] 

    for item in li1: li_copy.append(item) 

    return li_copy 

  

# Driver Code 

        a = [1, 2, 3] 

        b = Cloning(li1) 

        b[0] = 100

        

        print("Original List:", a) 

        print("After Cloning:", b)

Option 6:

# Using bilt-in method copy() 

def Cloning(li1): 

    li_copy =[] 

    li_copy = li1.copy() 

    return li_copy 

  

# Driver Code 

       a = [1, 2, 3] 

            b = Cloning(li1) 

            b[0] = 100

            

            print("Original List:", a) 

            print("After Cloning:", b)

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