Implemented and tested algorithm.

src/Assignments/A2/Substrings.java

@@ -33,9 +33,6 @@ Algorithm Design Block
         return counter, comps
 
     Big-O Analysis: (Based on Implementation)
-
-
-
 */
 package Assignments.A2;
 
@@ -50,6 +47,15 @@ import java.util.Scanner;
  */
 public class Substrings {
 
+    public static void main(String[] args) {
+        Substrings program = new Substrings();
+        program.start();
+    }
+
+    private String text;
+    private int subStringCount;
+    private int comparisons;
+
     /**
      * Used as the main sentential loop and loops until the exit option is selected.
      *
@@ -73,7 +79,19 @@ public class Substrings {
      * @param option the option that was chosen.
      */
     private void executeOption(int option) {
-        performAlgorithm();
+        if (option == 1) {
+            this.text = this.getString();
+        } else {
+            if (this.text == null) {
+                System.out.println("Please specify a text to perform the algorithm.");
+                return;
+            }
+            this.performAlgorithm();
+            System.out.println("Input string:       " + this.text);
+            System.out.println("# of substrings:    " + this.subStringCount);
+            System.out.println("# of comparisons:   " + this.comparisons);
+        }
+        System.out.println();
     }
 
     /**
@@ -83,7 +101,21 @@ public class Substrings {
      * @postcondition the results are generated.
      */
     private void performAlgorithm() {
+        this.subStringCount = 0;
+        this.comparisons = 0;
+        char[] values = this.text.toLowerCase().toCharArray();
 
+        for (int i = 0; i < this.text.length(); i++) {
+            if (values[i] == 'a') {
+                for (int j = i+1; j < this.text.length(); j++) {
+                    if (values[j] == 'b') {
+                        subStringCount++;
+                    }
+                    comparisons++;
+                }
+            }
+            comparisons++;
+        }
     }
 
     /**
@@ -124,6 +156,28 @@ public class Substrings {
         System.out.println();
     }
 
+    /**
+     * Gets a string and returns it. If the input is not valid it loops until valid.
+     *
+     * @precondition none
+     * @postcondition none
+     * @return a user-input text string.
+     */
+    private String getString() {
+        System.out.println("Specify a text to check number of substrings.");
+        System.out.print("Text: ");
+        Scanner sc = new Scanner(System.in);
+        String input = sc.nextLine();
+
+        while (input == null || input.isEmpty()) {
+            System.out.println("Please specify a valid text to check substrings.");
+            System.out.print("Text: ");
+            input = sc.nextLine();
+        }
+
+        return input;
+    }
+
     /**
      * Gets user input to a number. A prompt must be provided prior to running this method.
      * If the input was not an integer/(unable to be autoboxed), returns -1.
@@ -133,7 +187,7 @@ public class Substrings {
      *
      * @return the integer input, if invalid -1.
      */
-    protected int getIntegerInput() {
+    private int getIntegerInput() {
         Scanner sc = new Scanner(System.in);
         try {
             String textInput = sc.nextLine();