Question 300842 in Javascript Question posted in
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Javascript – Total sum recursion function

I’m trying to recursively go through an array, collect all the values and sum them. Any attempts to do this result in a stack overflow. Tell me how to implement a function 1) using an additional variable 2) without using an additional variable.

 const numbers = [
    {
        number: [
            {
                number: 3,
            },
            {
                number: [
                    {
                        number: 5
                    }
                ]
            },
        ]
    },
    {
        number: 8
    }
]

function getSumOfNumbers(numbers) {
    if (Array.isArray(numbers)) {
        for (const child of numbers) {
            getSumOfNumbers(child);
        }
    }
    if (!Array.isArray(numbers) && typeof (numbers) == 'object') {
        for (const key in numbers) {
            getSumOfNumbers(numbers[key]);
        }
    }
    if (typeof (numbers) == 'number') {
        return numbers + getSumOfNumbers(numbers);
    }
}

getSumOfNumbers(numbers)
Tags:

2

Answers


  1. Chosen as BEST ANSWER
    0

    I was able to return the sum of all values.

    function getSumOfNumbers(numbers) {
    if (typeof (numbers) == 'number') {
        return numbers;
    } else {
        let sum = 0;
        if (Array.isArray(numbers)) {
            for (const child of numbers) {
                sum += getSumOfNumbers(child);
            }
        }
        if (!Array.isArray(numbers) && typeof (numbers) == 'object') {
            for (const key in numbers) {
                sum += getSumOfNumbers(numbers[key]);
            }
        }
        return sum;
    }
}

    how to now implement the function without using an additional variable SUM?


  2. 0

    You mean just return the reduced values?

    const getSumOfNumbers = (numbers) => {
  if (typeof numbers === 'number') return numbers;
  else if (Array.isArray(numbers)) return numbers.reduce((acc, child) => acc + getSumOfNumbers(child), 0);
  else if (typeof numbers === 'object' && numbers !== null)  return Object.values(numbers).reduce((acc, value) => acc + getSumOfNumbers(value), 0);
  return 0;
};

console.log(getSumOfNumbers(numbers))
    <script>
  const numbers = [{
      number: [{
          number: 3,
        },
        {
          number: [{
            number: 5
          }]
        },
      ]
    },
    {
      number: 8
    }
  ]
</script>

    Terser

    const getSumOfNumbers = (numbers) => typeof numbers === 'number' ? numbers :
  (Array.isArray(numbers) || (typeof numbers === 'object' && numbers !== null)) ?
  Object.values(numbers).reduce((acc, value) => acc + getSumOfNumbers(value), 0) : 0;


console.log(getSumOfNumbers(numbers));
    <script>
const numbers = [
  {
    number: [
      {
        number: 3,
      },
      {
        number: [
          {
            number: 5
          }
        ]
      },
    ]
  },
  {
    number: 8
  },
  5,  // Simple number
  [1, 2, [3, 4]],  // Nested list
  {"a": 1, "b": 2, "c": {"d": 3, "e": 4}},  // Nested object
  [1, [2, [3, [4, [5]]]]],  // Deeply nested list
  {"a": 1, "b": {"c": 2, "d": {"e": 3, "f": 4}}},  // Deeply nested object
  [],  // Empty list
  {},  // Empty object
  null  // Null value
];

</script>
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