Question

How to reverse an array upto a given index in Node.js

Answer 1

function reverseUpToIndex(arr, index) {
	if (index > arr.length) {
        console.log("Index out of range");
        return;
    }
      
    for (let i = 0; i < index / 2; i++) {
        let temp = arr[i];
        arr[i] = arr[index - i - 1];
        arr[index - i - 1] = temp;            
    }
}


const arr = [ 3, 4, 9, 0, 7, 8, 5, 6 ];
         
const index = 5;
         
reverseUpToIndex(arr, index);
  
console.log(arr);

  
  
  
  
/*
run:
  
[ 7, 0, 9, 4, 3, 8, 5, 6 ]
  
*/

 

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