Largest and Lowest Number of the Array using JavaScript

  let array_1 = [7, 9, 3, 2, 0, 10, 90, 21, 12, 87, 11, 22, 8];
    let array_2 = [7, 9, 3, 2, 0, 10, 90, 21, 12, 87, 11, 22, 8, 4, 1, 0];
   
    let largest_number = array_1[0];
    let lowest_number = array_2[0];

    // loop to find largest number of the array..
    for(var i=0; i<array_1.length; i++){
             if(largest_number<array_1[i]){
                   largest_number = array_1[i];
             }
    }

    // loop to find lowest number of the array..

    for(var k=0; k<array_2.length; k++){
             if(lowest_number > array_2[k]){
                   lowest_number = array_2[k];
             }
    }    

    console.log(largest_number);
    console.log(lowest_number);