refactoring: entry-into-switch

src/main/c/Calculator/calculator.c

@@ -70,56 +70,11 @@ double combination(int n, int r);
         printf("19. Combination\n");
         printf("20. Exit\n");
     }
-    double add(double num1, double num2) {
-        return num1 + num2;
-    }
-
-    double subtract(double num1, double num2) {
-        return num1 - num2;
-    }
-    double multiply(double num1, double num2) {
-        return num1 * num2;
-    }
-    double divide(double num1, double num2) {
-        return num1 / num2;
-    }
-
-    double exponent(double base, double exponent) {
-        return pow(base, exponent);
-    }
-
-    double modulus(double num1, double num2) {
-        return fmod(num1, num2);
-    }
+    double performOperation(int choice, double num1, double num2) {
+    switch (choice) {
 
-    double logarithm(double num) {
-        return log(num);
-    }
-
-    double potential(double base, double exponent) {
-        return pow(base, exponent);
-    }
-    double squareRoot(double num) {
-        return sqrt(num);
-    }
 
-    double square(double num) {
-        return num * num;
-    }
-
-    double cube(double num) {
-        return num * num * num;
-    }
 
-    double cubeRoot(double num) {
-        return cbrt(num);
-    }double factorial(double num) {
-        if (num == 0) {
-            return 1;
-        } else {
-            return num * factorial(num - 1);
-        }
-    }
 
     double power(double base, double exponent) {
         return pow(base, exponent);