Question

How to check if an array contains duplicates in JavaScript

Answer 1

function arrayContainsDuplicates(array) {
  	if (array.length !== new Set(array).size) {
    	  return true;
  	}

  	return false;
}

const arr1 = ['javascript', 'typescript', 'node.js', 'javascript'];
console.log(arrayContainsDuplicates(arr1));

const arr2 = ['c', 'javascript', 'c++'];
console.log(arrayContainsDuplicates(arr2));

  
  
  
  
/*
run:
  
true
false
  
*/

 

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