Added test cases in krishnamurthy.c

math/krishnamurthy.c

@@ -1,29 +1,39 @@
-#include <stdio.h>
+#include <stdio.h> // For I/O ops
+#include <assert.h> //For test cases
 
-/*
-
- * A krishnamurthy number is a number where the sum of 
- the factorial of its digits is equal to the number itself
+/**
+MAIN DESCRIPTION:
 
- For example, 145 = 1! + 4! + 5!
- but 13 != 1! + 3!
+ * @description a krishnamurthy number is
+ * a number whose sum of the factorial of digits
+ * is equal to the number itself.
 
- * For more information, visit https://www.geeksforgeeks.org/problems/krishnamurthy-number1323/1
+ * @example 145 = 1! + 4! + 5!
 
+ * @reference https://www.geeksforgeeks.org/problems/krishnamurthy-number1323/1
 */
 
 
+/**
+ * @description n! = n*(n-1)*(n-2)*...*1
+ * @brief calculates the factorial of a number
+ * @param n the number we want to calculate the factorial
+ * @return an integer representing the factorial of n
+ */
 int factorial(int n){
-    //Simple function returning the factorial of n
-
     if (n<2){
 	return n;
     }
     return n*factorial(n-1);
 }
 
+/**
+ * @brief Calculates the sum of the factorial of each digit
+ * @param n the number to calculate the sum of the factorial of its digits
+ * @param sum the sum variable to be incremented 
+ * @returns an integer representing that sum
+ */
 int get_digit(int n, int sum){
-    // Function returning the sum of the factorial of the digits
 
     if (n<10){
 	return sum+factorial(n);
@@ -35,21 +45,33 @@ int get_digit(int n, int sum){
     }
 }
 
-void krishnamurthy(int n){
+/*
+ * @brief Verifies if a given number
+ * is a krishnamurthy number
+ * @param n the number to be verified as a krishnamurthy number
+ * @returns 1 if n is a krishnamurthy number
+ * @returns 0 if n is not a krishnamurthy number
+ */
+int krishnamurthy(int n){
     int sum=0;
-    if (get_digit(n,sum)==n){
-	printf("%d is a krishnamurthy number\n",n);
-    }
-    else {
-	printf("%d is not a krishnamurthy number\n",n);
-    }
+    return get_digit(n,sum)==n;
+}
+
+/**
+ * @brief Implementation of test cases
+ * @return void
+ */
+static void tests(){
+    assert(krishnamurthy(1) == 1);
+    assert(krishnamurthy(13) == 0);
+    assert(krishnamurthy(45) == 0);
+    assert(krishnamurthy(145) == 1);
+    assert(krishnamurthy(239) == 0);
+    printf("All tests were successful!\n");
 }
 
 int main(){
-    int n = 13, x = 145;
-    printf("For example: \n");
-    krishnamurthy(n);
-    krishnamurthy(x);
+    tests();
     return 0;
 }