how to modify an array javascript code example

Example 1: modify array elements javascript

Using a FOR loop, write a function addNumber which adds the argument n to each 
number in the array arr and returns the updated arr:
const addNumber=(arr, n)=>{  
  let arr1=[];
  for(let i=0;i<Math.max(arr.length);i++){
    arr1.push((arr[i]||0)+n)
  }
  return arr1;
} 
console.log(addNumber([4, 5, 6], 7)); // expected log [11, 12, 13]

Example 2: how to modify an array

let browsers = ['chrome', 'firefox', 'edge'];
browsers.push('safari', 'opera mini');
console.log(browsers); 
// ["chrome", "firefox", "edge", "safari", "opera mini"]