C# - Jagged Arrays

A Jagged array is an array of arrays. You can declare a jagged array scores of int values as:

int [][] scores;

Declaring an array, does not create the array in memory. To create the above array:

int[][] scores = new int[5][];
for (int i = 0; i < scores.Length; x++) 
{
   scores[i] = new int[4];
}

You can initialize a jagged array as:

int[][] scores = new int[2][]{new int[]{92,93,94},new int[]{85,66,87,88}};

Where, scores is an array of two arrays of integers -- scores[0] is an array of 3 integers and scores[1] is an array of 4 integers.

Example

The following example illustrates using a jagged array:

using System;

namespace ArrayApplication
{
    class MyArray
    {
        static void Main(string[] args)
        {
            /* a jagged array of 5 array of integers*/
            int[][] a = new int[][]{new int[]{0,0},new int[]{1,2}, 
            new int[]{2,4},new int[]{ 3, 6 }, new int[]{ 4, 8 } }; 

            int i, j;

            /* output each array element's value */
            for (i = 0; i < 5; i++)
            {
                for (j = 0; j <; 2; j++)
                {
                    Console.WriteLine("a[{0}][{1}] = {2}", i, j, a[i][j]);
                }
            }
           Console.ReadKey();
        }
    }
}

When the above code is compiled and executed, it produces following result:

a[0][0]: 0
a[0][1]: 0
a[1][0]: 1
a[1][1]: 2
a[2][0]: 2
a[2][1]: 4
a[3][0]: 3
a[3][1]: 6
a[4][0]: 4
a[4][1]: 8