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Recursion Function Basics
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Recursion Function Basics

EasyPython

Problem

A BILL approval policy may contain individual approval thresholds and nested approval groups. Given a nested structure of integers, return the sum of every integer using recursion.

An element is either an integer or a list containing more valid elements. The function must recursively process each nested list and add all integer values.

Formal Specification

Implement sum_nested_values(items):

  • Input: items, a non-empty nested list containing integers or lists of valid nested elements.
  • Output: An integer representing the sum of all integers in items.
  • Do not use string conversion or flatten the structure before summing.

Constraints

  • 1 <= number of elements in the structure <= 10^4
  • -10^6 <= each integer <= 10^6
  • Maximum nesting depth is 100
  • Empty nested lists are valid

Function Signature

def sum_nested_values(items):
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