I need condition to be true only if all properties of the object (variables) are not equal to each other. How can I condition object properties' inequality in a more optimal way? If the number of them grows the combination of obj[1]!=obj[2] and so on will grow enormously

var obj = {
                1: linksArray[randomNumber],
                2: linksArray[randomNumber2],
                3: linksArray[randomNumber3]
            } 
                    
            if(obj[1]!=obj[2] && obj[1]!=obj[3] &&
                obj[2]!=obj[3] && obj[2]!=obj[1] &&
                obj[3]!=obj[2] && obj[3]!=obj[1]
                ) {
                    arr.push(linksArray[randomNumber]);
                    arr.push(linksArray[randomNumber2]);
                    arr.push(linksArray[randomNumber3]);
                    break;
                }  

CodePudding user response：

Get the object's values, and create a Set. If the Set's size is identical to the values length, all values are unique:

const allUnique = obj => {
  const values = Object.values(obj)
  
  return new Set(values).size === values.length
}

const obj1 = { 1: 'a', '2': 'b', 3: 'c' }
const obj2 = { 1: 'a', '2': 'b', 3: 'c', 4: 'b' }

console.log(allUnique(obj1)) // true
console.log(allUnique(obj2)) // false

<iframe name="sif1" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

Put all the values in an array, then use it to build a Set (data structure where all items are different, documentation).

If the array has the same amount of items as the set, you're sure they're all different.

var obj1 = {
  field1: true,
  fiedl2: 2,
  field3: "red",
}

var obj2 = {
  field1: true,
  fiedl2: 2,
  field3: "red",
  field4: 2
}

function allDifferent(obj) {
  const values = Object.values(obj);
  return new Set(values).size === values.length
}

console.log(allDifferent(obj1));
console.log(allDifferent(obj2));

<iframe name="sif2" sandbox="allow-forms allow-modals allow-scripts" frameborder="0"></iframe>

CodePudding user response：

Check for duplicates by making a Set of all the object values - these will be unique. Then compare the size of the Set to the number of key/values in the original object. If they are different - there is a duplicate in the original. If they are the same, the values of the original are unique.

const uniqueValues = new Set(Object.keys(obj));
if (uniqueValues.size == obj.length) {...do stuff}

CodePudding user response：

Check out this guy: https://medium.com/@weberzt/finding-duplicate-integers-in-an-array-in-javascript-4fa9f0f3c45

Very interesting solution. In this solution the a type is an array.

function containsDuplicates(a) {
  return (new Set(a)).size !== a.length;
}

Complexity is O(n) which is not bad