Golang Program to Calculate The Power using Recursion

In this tutorial, we will learn how to calculate the power using recursion technique in Go programming language.

Power can be defined as a number being multiplied by itself a specific number of times.

Exponent can be defined to the number of times a number is used in a multiplication. Powers and exponents are important tools to rewrite long multiplication problems in mathematics, especially in algebra.

Example: 24 = 2 × 2 × 2 × 2 = 16, where 2 is the base and 4 is the exponent.

A Recursion is where a function calls itself by direct or indirect means. Every recursive function has a base case or base condition which is the final executable statement in recursion and halts further calls.

Below we have shown examples with two different kinds of recursion methods.

Example 1: Golang Program Code to calculate the power using Direct Recursion Method

Syntax

Result = (num * POWER(num, power-1)
// Recursive function call to the function POWER() by itself up to the defined condition

Algorithm

• Step 1 − Import the package fmt.

• Step 2 − Create the function POWER().

• Step 3 − We will use an if-conditional statement.

• Step 4 − Recursive call to the function itself.

• Step 5 − Start the function main().

• Step 6 − Declare and initialize the variables.

• Step 7 − Call the function POWER ().

• Step 8 − Print the result on the screen using fmt.Printf().

Example

// GOLANG PROGRAM TO CALCULATE THE POWER USING RECURSION
// Direct Recursion example
package main

// fmt package provides the function to print anything
import "fmt"

// create a function
func POWER(num int, power int) int {
   var result int = 1
   if power != 0 {
   
      // Recursive function call to itself
      result = (num * POWER(num, power-1))
   }
   return result
}
func main() {
   fmt.Println("Golang Program to calculate the power using recursion")
   // declare and initialize the integer variables
   var base int = 4
   var power int = 2
   var result int
   
   // calling the POWER() function
   result = POWER(base, power)
   
   // Print the result using in-built function fmt.Printf()
   fmt.Printf("%d to the power of %d is: %d\n", base, power, result)
}

Output

Golang Program to calculate the power using recursion
4 to the power of 2 is: 16

Description of the Code

• In the above program, we first declare the package main.

• We imported the fmt package that includes the files of package fmt

• Next we create a function POWER() to calculate the power using direct recursion technique

• We will use an if conditional statement which allows you to execute one block of code if the specified condition is true and then recursive call to the function itself

• Now start the function main().GO program execution starts with the function main(). Declare the integer variables base, power and result

• Now calling the POWER() function

• And finally printing the result on the screen using in-built function fmt.Printf().This function is defined under the fmt package and it helps to write standard output.

Example 2: Golang Program code to calculate the Power using Indirect Recursion Method

Syntax

func recursion_1() {
   recursion_2()}
func recursion_2(){
   recursion_1()}
func main() {
   recursion_1();
}

Algorithm

• Step 1 − Import the package fmt.

• Step 2 − Create the function POWER_1().

• Step 3 − We will use an if−conditional statement.

• Step 4 − Recursive call to the function POWER_2().

• Step 5 − Create the function POWER_2().

• Step 6 − Recursive call to the function POWER_1() indirectly.

• Step 7 − Start the function main().

• Step 8 − Declare and initialize the variables.

• Step 9 − Call the function POWER_2 ().

• Step 10 − Print the result on the screen using fmt.Printf().

Example

// GOLANG PROGRAM TO CALCULATE THE POWER USING RECURSION
// Indirect Recursion example
package main

// fmt package provides the function to print anything
import "fmt"

// create a first Recursive function
func POWER_1(num int, power int) int {
   var result int = 1
   if power != 0 {
   
      // Recursive function call to the second function
      result = (num * POWER_2(num, power-1))
   }
   return result
}
// create a second Recursive function
func POWER_2(num int, power int) int {
   var result int = 1
   if power != 0 {
   
      // Recursive function call to the first function
      // which calls this first function indirectly
      result = (num * POWER_1(num, power-1))
   }
   return result
}
func main() {
   fmt.Println("Golang Program to calculate the power using recursion")
   // declare and initialize the integer variables
   var base int = 5
   var power int = 2
   var result int
   
   // calling the POWER_2() function
   result = POWER_2(base, power)
   
   // Print the result using in-built function fmt.Printf()
   fmt.Printf("%d to the power of %d is: %d\n", base, power, result)
}

Output

Golang Program to calculate the power using recursion
5 to the power of 2 is: 25

Description of the Code

• In the above program, we first declare the package main.

• We imported the fmt package that includes the files of package fmt.

• Next we create a function POWER_1() to calculate the power using indirect recursion technique.

• We will use an if conditional statement which allows you to execute one block of code if the specified condition is true and then recursive call to the second function POWER_2().

• Next we create a function POWER_2 (). Here recursive function call to the first function is made which calls the first function POWER_1() indirectly.

• Now start the function main().GO program execution starts with the function main().

• Declare the integer variables base, power and result.

• Now calling the POWER_2() function.

• And finally printing the result on the screen using in-built function fmt.Printf().This function is defined under the fmt package and it helps to write standard output.

Conclusion

In the above two examples we have successfully complied and executed Golang Program code to calculate the power using the recursion technique. In the first example we have shown direct recursion method and in the second example we have shown indirect recursion method.