Finished exercise 3-2. Starting 3.5

ch_03/switch/main.c

@@ -0,0 +1,75 @@
+/*
+ *
+ * The program demonstrates the use of the switch statement while counting
+ * the occurrences of digits, white spaces (including actual white space,
+ * new line, and a tab character), and other types of characters
+ *
+ * Author: Kun Deng
+ */
+
+#include <stdio.h>
+
+
+#define ARRAY_SIZE 13
+
+int main()
+{
+    int c, white_space_count, other_character_count;
+    int digit_count[ARRAY_SIZE];
+
+    white_space_count = other_character_count = 0;
+
+    for (int i = 0; i < ARRAY_SIZE; ++i)
+    {
+        digit_count[i] = 0;
+    }
+
+    while ((c = getchar()) != EOF)
+    {
+        switch (c)
+        {
+        case '0':
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7':
+        case '8':
+            // If no break statement is provided in a case then
+            // the code can continue to execute other cases where
+            // the expression matches the case.
+        case '9':
+            ++digit_count[c - '0'];
+            // Break statements causes the control flow of the program
+            // to exit out of the block of code. In this case the
+            // break statement will cause the control flow to exit
+            // from the switch statement
+            break;
+        case ' ':
+        case '\n':
+        case '\t':
+            ++white_space_count;
+            break;
+        default:
+            // Good practice to have a default case and have a break statement.
+            // Just in case more cases are added to the future
+            ++other_character_count;
+            break;
+        }
+    }
+
+    printf("Digits =");
+
+    for (int i = 0; i < ARRAY_SIZE; ++i)
+    {
+        printf(" %d", digit_count[i]);
+    }
+
+    printf(", white space = %d, other = %d\n", 
+            white_space_count, other_character_count);
+
+
+    return 0;
+}