# Python: Sum two or more lists, the lengths of the lists may be different

## Python List: Exercise - 194 with Solution

Write a Python program to sum two or more lists. The lengths of the lists may be different.

**Visual Presentation: **

**Sample Solution:**

**Python Code:**

```
# Define a function called 'sum_lists_diff_length' that calculates the sum of lists with different lengths.
def sum_lists_diff_length(test_list):
# Create a result list using a list comprehension.
# 1. For each sublist 'x' in 'test_list', calculate the sum of its elements.
# 2. Use 'zip(*map(...))' to ensure that all sublists have the same length by padding shorter sublists with zeros.
result = [sum(x) for x in zip(*map(lambda x: x + [0] * max(map(len, test_list)) if len(x) < max(map(len, test_list)) else x, test_list))]
return result # Return the list of sums.
# Create a list of lists 'nums', where each sublist contains integers.
nums = [[1, 2, 4], [2, 4, 4], [1, 2]]
# Print a message indicating the original list of lists.
print("\nOriginal list:")
# Print the original list 'nums'.
print(nums)
# Print a message indicating the sum of lists with different lengths.
print("Sum said lists with different lengths:")
# Call the 'sum_lists_diff_length' function with 'nums' and print the result (sums of sublists).
print(sum_lists_diff_length(nums))
# Create another list of lists 'nums' with different lengths.
nums = [[1], [2, 4, 4], [1, 2], [4]]
# Print a message indicating the original list of lists.
print("\nOriginal list:")
# Print the original list 'nums'.
print(nums)
# Print a message indicating the sum of lists with different lengths.
print("Sum said lists with different lengths:")
# Call the 'sum_lists_diff_length' function with 'nums' and print the result (sums of sublists).
print(sum_lists_diff_length(nums))
```

Sample Output:

Original list: [[1, 2, 4], [2, 4, 4], [1, 2]] Sum said lists with different lengths: [4, 8, 8] Original list: [[1], [2, 4, 4], [1, 2], [4]] Sum said lists with different lengths: [8, 6, 4]

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