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Python: Add two given lists of different lengths, start from left

Python List: Exercise - 155 with Solution

Write a Python program to add two given lists of different lengths, start from left.

Sample Solution:

Python Code:

def elementswise_left_join(l1, l2):
    f_len = len(l1)-(len(l2) - 1)
    for i in range(0, len(l2), 1):
        if f_len - i >= len(l1):
            break
        else:
            l1[i] = l1[i] + l2[i]
    return l1

nums1 = [2, 4, 7, 0, 5, 8]
nums2 = [3, 3, -1, 7]
print("\nOriginal lists:")
print(nums1)
print(nums2)
print("\nAdd said two lists from left:")
print(elementswise_left_join(nums1,nums2))

nums3 = [1, 2, 3, 4, 5, 6]
nums4 = [2, 4, -3]
print("\nOriginal lists:")
print(nums3)
print(nums4)
print("\nAdd said two lists from left:")
print(elementswise_left_join(nums3,nums4))

Sample Output:

Original lists:
[2, 4, 7, 0, 5, 8]
[3, 3, -1, 7]

Add said two lists from left:
[5, 7, 6, 7, 5, 8]

Original lists:
[1, 2, 3, 4, 5, 6]
[2, 4, -3]

Add said two lists from left:
[3, 6, 0, 4, 5, 6]

Flowchart:

Flowchart: Add two given lists of different lengths, start from left.

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Python Code Editor:

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Previous: Write a Python program to join two given list of lists of same length, element wise.
Next: Write a Python program to add two given lists of different lengths, start from right.

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Python: Tips of the Day

Big Number Readability:

you can separate zeros with underscore (_)

print(2_000_000)
print(2_000_000 +1)

Output:

2000000
2000001