Consider a JavaScript function generateCombinations(obj) designed to generate all possible combinations of values for a given input object obj. The objective is to replace values within arrays and nested objects with null to cover all possible combinations. The provided function is intended to handle cases where objects are present as elements within arrays. Here are the statements related to the function:
The function initializes an array result to store the generated combinations.
The function uses recursion and iterates through the keys of the input object to generate combinations.
If the current value of a key is an array, the function iterates through each element and considers cases where the element is an object or a simple value.
For arrays with objects as elements, the function correctly generates combinations by setting object properties to their values or null.
The function handles cases where arrays might be empty, generating combinations with an empty array or an array containing a null element.
If the current value of a key is a nested object (not an array), the function generates combinations by replacing nested values with null.
The function sets absent keys to null in nested objects to ensure all keys are covered in the combinations.
The generated combinations are pushed to the result array and returned as the final output.
Your task is to review the provided JavaScript function and its statements and identify any issues or improvements needed to ensure it correctly handles cases where objects are present as elements within arrays.
Or Write your own function for this problem stating and make sure the function covers all the points
const fs = require('fs');
function generateCombinations(obj) {
const keys = Object.keys(obj);
const result = [];
function generate(index, currentCombination) {
if (index === keys.length) {
// Set absent keys to null in nested objects
Object.keys(obj).forEach((key) => {
if (!(key in currentCombination)) {
currentCombination[key] = null;
}
});
result.push(currentCombination);
return;
}
const currentKey = keys[index];
const currentValue = obj[currentKey];
if (Array.isArray(currentValue)) {
if (currentValue.length > 0) {
currentValue.forEach((arrayElement, arrayIndex) => {
if (typeof arrayElement === 'object' && arrayElement !== null) {
const arrayElementKeys = Object.keys(arrayElement);
arrayElementKeys.forEach((arrayElementKey) => {
const arrayElementValue = arrayElement[arrayElementKey];
generate(index + 1, {
...currentCombination,
[currentKey]: [
...(currentCombination[currentKey] || []).slice(0, arrayIndex),
{
...(currentCombination[currentKey] || [])[arrayIndex] || {},
[arrayElementKey]: arrayElementValue,
},
...(currentCombination[currentKey] || []).slice(arrayIndex + 1),
],
});
generate(index + 1, {
...currentCombination,
[currentKey]: [
...(currentCombination[currentKey] || []).slice(0, arrayIndex),
{
...(currentCombination[currentKey] || [])[arrayIndex] || {},
[arrayElementKey]: null,
},
...(currentCombination[currentKey] || []).slice(arrayIndex + 1),
],
});
});
} else {
generate(index + 1, {
...currentCombination,
[currentKey]: [
...(currentCombination[currentKey] || []).slice(0, arrayIndex),
arrayElement,
...(currentCombination[currentKey] || []).slice(arrayIndex + 1),
],
});
generate(index + 1, {
...currentCombination,
[currentKey]: [
...(currentCombination[currentKey] || []).slice(0, arrayIndex),
null,
...(currentCombination[currentKey] || []).slice(arrayIndex + 1),
],
});
}
});
} else {
// Handle empty arrays
generate(index + 1, {
...currentCombination,
[currentKey]: [],
});
}
} else if (typeof currentValue === 'object' && currentValue !== null) {
const nestedKeys = Object.keys(currentValue);
nestedKeys.forEach((nestedKey) => {
const nestedValue = currentValue[nestedKey];
// Generate combinations with nested key and its value
generate(index + 1, {
...currentCombination,
[currentKey]: {
...(currentCombination[currentKey] || {}),
[nestedKey]: nestedValue,
},
});
// Generate combinations with nested key set to null
generate(index + 1, {
...currentCombination,
[currentKey]: {
...(currentCombination[currentKey] || {}),
[nestedKey]: null,
},
});
});
} else {
// Generate combinations with current key and its value
generate(index + 1, {
...currentCombination,
[currentKey]: currentValue,
});
// Generate combinations with current key set to null
generate(index + 1, {
...currentCombination,
[currentKey]: null,
});
}
}
generate(0, {});
return result;
}
// Example JSON object with arrays containing objects
// Generate combinations
const combinations = generateCombinations(inputObject);
// Convert combinations to JSON string
const jsonString = JSON.stringify(combinations, null, 2);
// Write to a file
fs.writeFileSync('Queue/output.json', jsonString, 'utf-8');
console.log('Output file created: output.json');
for this input const inputObject = {
key1: [1, 2],
key2: {
nested1: 'a',
nested2: ['x', 'y'],
},
key3: 'value3',
};
If you are getting this type of output then your code is correct
[
{
key1: [1, 2],
key2: { nested1: 'a', nested2: ['x', 'y'] },
key3: 'value3'
},
{
key1: [1, 2],
key2: { nested1: 'a', nested2: ['x', null] },
key3: 'value3'
},
// (other combinations)
{
key1: [1, 2],
key2: { nested1: null, nested2: ['x', 'y'] },
key3: 'value3'
},
{
key1: [1, 2],
key2: { nested1: null, nested2: ['x', null] },
key3: 'value3'
},
// (other combinations)
{
key1: null,
key2: { nested1: 'a', nested2: ['x', 'y'] },
key3: 'value3'
},
{
key1: null,
key2: { nested1: 'a', nested2: ['x', null] },
key3: 'value3'
},
// (other combinations)
{
key1: null,
key2: { nested1: null, nested2: ['x', 'y'] },
key3: 'value3'
},
{
key1: null,
key2: { nested1: null, nested2: ['x', null] },
key3: 'value3'
},
]
