Merge pull request #1 from kdeng00/ch05

Pointer arithmetic example

ch_05/pointer_arithmetic/main.c

@@ -0,0 +1,69 @@
+/*
+ *
+ * Demonstration of pointer arithmetic
+ *
+ * Author: Kun Deng
+ */
+
+#include <stdio.h>
+
+#define ARRAY_SIZE 10
+
+
+void populate_array(int some_array[])
+{
+    for (int i = 0; i < ARRAY_SIZE; ++i)
+    {
+        some_array[i] = 100 - (i * 1.5);
+    }
+}
+
+void print_array(int some_array[])
+{
+    for (int i = 0; i < ARRAY_SIZE; ++i)
+    {
+        const int value = some_array[i];
+
+        if (i == 0)
+        {
+            printf("%d", value);
+        }
+        else
+        {
+            printf(" %d", value);
+        }
+    }
+
+    printf("\n");
+}
+
+// 1 if true and 0 if not
+int pointer_precedes(int *a, int *b)
+{
+    return a < b;
+}
+
+int main()
+{
+    printf("pointer_arithmetic\n");
+
+    int some_array[ARRAY_SIZE];
+    populate_array(some_array);
+    print_array(some_array);
+
+    const int a_index = 1;
+    const int b_index = 2;
+
+    int *a = &some_array[a_index];
+    int *b = &some_array[b_index];
+
+    printf("a is th %d position with value %d\n", a_index, *a);
+    printf("b is th %d position with value %d\n", b_index, *b);
+
+    const int result = pointer_precedes(a, b);
+
+    printf("Result: %d\n", result);
+
+
+    return 0;
+}