34 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			34 lines
		
	
	
		
			1.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
|   | --- | ||
|  | title: Catch Unclosed Parentheses, Brackets, Braces and Quotes | ||
|  | --- | ||
|  | ## Catch Unclosed Parentheses, Brackets, Braces and Quotes
 | ||
|  | 
 | ||
|  | The reduce() method reduces an array to a single value.  If you're not familiar with it, the following code shows an example of using the the method: | ||
|  | 
 | ||
|  | ``` | ||
|  | const array1 = [1, 2, 3, 4]; | ||
|  | console.log(array1.reduce((accumulator, currentValue) => accumulator + currentValue));  // expected output: 10 | ||
|  | ``` | ||
|  | You can also define the argument to the reduce method as a variable or constant and hand that in to the function, e.g., | ||
|  | 
 | ||
|  | ``` | ||
|  | const array1 = [1, 2, 3, 4]; | ||
|  | const reducer = (accumulator, currentValue) => accumulator + currentValue; | ||
|  | 
 | ||
|  | // 1 + 2 + 3 + 4 | ||
|  | console.log(array1.reduce(reducer));      // expected output: 10 | ||
|  | 
 | ||
|  | // 5 + 1 + 2 + 3 + 4 | ||
|  | console.log(array1.reduce(reducer, 5));   // expected output: 15 | ||
|  | ``` | ||
|  | 
 | ||
|  | You can see and run this code at [Array.prototype.reduce()](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/reduce). | ||
|  | 
 | ||
|  | ## Solution:
 | ||
|  | 
 | ||
|  | ```javascript | ||
|  | let myArray = [1, 2, 3]; | ||
|  | let arraySum = myArray.reduce((previous, current) =>  previous + current); | ||
|  | console.log(`Sum of array values is: ${arraySum}`); | ||
|  | ``` |