Recall that there are three steps for using arrays:
- Declare the array (declare a variable whose type is an array)
- Instantiate the array (allocate memory for the array)
- Initialize the array (store values in the array)
Below are examples of the different ways that you can declare, instantiate, and initialize an array.
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| // Option 1: Declare, instantiate and initialize in three// stepsint[] a1;a1 = new int[3];a1[0] = 1; a1[1] = 2; a1[2] = 3;// Option 2: Declare in 1 step, instantiate/initialize in// 2nd stepint[] a2;a2 = new int[] {1, 2, 3};// Option 3: Declare and instantiate in 1 step,// initialize later.int[] a3 = new int[3]; // Must provide sizea3[0] = 1; a3[1] = 2; a3[2] = 3;// Option 4: Declare, instantiate and initialize// in single line. (Using array initializer)int[] a4 = new int[] { 1, 2, 3 };// Variation: Can omit typeint[] a5 = new[] { 1, 2, 3 };// Variation: Can omit new keyword, inferring typeint[] a6 = { 1, 2, 3 }; |