Question

Assume you are given an int variable named nPositive and a two-dimensional array of ints that has been created and assigned to a2d. Write some statements that compute the number of all the elements in the entire two-dimensional array that are greater than zero and assign the value to nPositive.

Answer 1

Answer:

public class Main

{

public static void main(String[] args) {

    int nPositive = 0;

    int[][] a2d = {{-7,28, 92}, {0,11,-55}, {109, -25, -733}};

 for (int i = 0; i < a2d.length; i++) {

                  for(int j = 0; j < a2d[i].length; j++) {

         if(a2d[i][j] > 0){

             nPositive++;

                       }

                  }

 }

 System.out.println(nPositive);

}

}

Explanation:

*The code is in Java.

Initialize the nPositive as 0

Initialize a two dimensional array called a2d

Create a nested for loop to iterate through the array. If an element is greater than 0, increment the nPositive by 1

When the loop is done, print the nPositive

Answer 2

Answer:

const a2d =  [[7,28, 92], [0,11,-55], [109, -25, -733]];

let nPositive = a2d.reduce((a,c) => a + c.filter(n => n>0).length, 0);

console.log(nPositive);

Explanation:

Just for fun, I want to share the solution in javascript when using the powerful list operations. It is worthwhile learning to understand function expressions and the very common map(), reduce() and filter() primitives!