# Python | Sum two unequal length lists in cyclic manner

Given two unequal length lists, the task is to add elements of two list such that when elements of smaller list are over, add elements in a circular manner till all element of the larger list is iterated.

Let’s discuss different ways we can do this task.

Method #1 : Using Iteratools and zip

 `# Python code to add two different ` `# length lists in cyclic manner ` ` `  `# Importing ` `from` `itertools ``import` `cycle ` ` `  `# List initialization ` `list1 ``=` `[``150``, ``177``, ``454``, ``126``] ` `list2 ``=` `[``9``, ``44``, ``2``, ``168``, ``66``, ``80``, ``123``, ``6``, ``180``, ``184``] ` ` `  `# Using zip ` `output ``=` `[x ``+` `y ``for` `x, y ``in` `zip``(cycle(list1), list2)] ` ` `  `# Printing output ` `print``(output) `

Output:

```[159, 221, 456, 294, 216, 257, 577, 132, 330, 361]
```

Method #2 : Using Iteratools and starmap

 `# Python code to add two different  ` `# length lists in cyclic manner ` ` `  `# Importing ` `from` `itertools ``import` `starmap, cycle ` `from` `operator ``import` `add ` ` `  `# List initialization ` `list1 ``=` `[``150``, ``177``, ``454``, ``126``] ` `list2 ``=` `[``9``, ``44``, ``2``, ``168``, ``66``, ``80``, ``123``, ``6``, ``180``, ``184``] ` ` `  `# Using starmap ` `output ``=` `list``(starmap(add, ``zip``(cycle(list1), list2))) ` ` `  `# Print output ` `print``(output) `

Output:

```[159, 221, 456, 294, 216, 257, 577, 132, 330, 361]
```

Method #3 : Using List comprehension

 `# Python code to add two different ` `# length lists in cyclic manner ` ` `  `# List initialization ` `list1 ``=` `[``150``, ``177``, ``454``, ``126``] ` `list2 ``=` `[``9``, ``44``, ``2``, ``168``, ``66``, ``80``, ``123``, ``6``, ``180``, ``184``] ` ` `  `# List comprehension ` `output ``=` `[list1[i ``%` `len``(list1)]``+``list2[i] ` `             ``for` `i ``in` `range``(``len``(list2))] ` ` `  `# Printing output ` `print``(output) `

Output:

```[159, 221, 456, 294, 216, 257, 577, 132, 330, 361]
```

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