Skip to content
Related Articles

Related Articles

Improve Article

Write you own Power without using multiplication(*) and division(/) operators

  • Difficulty Level : Easy
  • Last Updated : 07 Apr, 2021

Method 1 (Using Nested Loops)
We can calculate power by using repeated addition. 
For example to calculate 5^6. 
1) First 5 times add 5, we get 25. (5^2) 
2) Then 5 times add 25, we get 125. (5^3) 
3) Then 5 time add 125, we get 625 (5^4) 
4) Then 5 times add 625, we get 3125 (5^5) 
5) Then 5 times add 3125, we get 15625 (5^6) 

C++




// C++ code for power function
#include <bits/stdc++.h>
using namespace std;
 
/* Works only if a >= 0 and b >= 0 */
int pow(int a, int b)
{
    if (b == 0)
        return 1;
    int answer = a;
    int increment = a;
    int i, j;
    for(i = 1; i < b; i++)
    {
        for(j = 1; j < a; j++)
        {
            answer += increment;
        }
        increment = answer;
    }
    return answer;
}
 
// Driver Code
int main()
{
    cout << pow(5, 3);
    return 0;
}
 
// This code is contributed
// by rathbhupendra

C




#include<stdio.h>
/* Works only if a >= 0 and b >= 0  */
int pow(int a, int b)
{
  //base case : anything raised to the power 0 is 1
  if (b == 0)
    return 1;
  int answer = a;
  int increment = a;
  int i, j;
  for(i = 1; i < b; i++)
  {
     for(j = 1; j < a; j++)
     {
        answer += increment;
     }
     increment = answer;
  }
  return answer;
}
 
/* driver program to test above function */
int main()
{
  printf("\n %d", pow(5, 3));
  getchar();
  return 0;
}

Java




import java.io.*;
 
class GFG {
     
    /* Works only if a >= 0 and b >= 0 */
    static int pow(int a, int b)
    {
        if (b == 0)
            return 1;
             
        int answer = a;
        int increment = a;
        int i, j;
         
        for (i = 1; i < b; i++) {
            for (j = 1; j < a; j++) {
                answer += increment;
            }
            increment = answer;
        }
         
        return answer;
    }
 
    // driver program to test above function
    public static void main(String[] args)
    {
        System.out.println(pow(5, 3));
    }
}
 
// This code is contributed by vt_m.

Python




# Python 3 code for power
# function
 
# Works only if a >= 0 and b >= 0
def pow(a,b):
    if(b==0):
        return 1
         
    answer=a
    increment=a
     
    for i in range(1,b):
        for j in range (1,a):
            answer+=increment
        increment=answer
    return answer
 
# driver code
print(pow(5,3))
 
# this code is contributed
# by Sam007

C#




using System;
 
class GFG
{
    /* Works only if a >= 0 and b >= 0 */
    static int pow(int a, int b)
    {
        if (b == 0)
            return 1;
             
        int answer = a;
        int increment = a;
        int i, j;
         
        for (i = 1; i < b; i++) {
            for (j = 1; j < a; j++) {
                answer += increment;
            }
            increment = answer;
        }
         
        return answer;
    }
 
    // driver program to test
    // above function
    public static void Main()
    {
        Console.Write(pow(5, 3));
    }
}
 
// This code is contributed by Sam007

PHP




<?php
 
// Works only if a >= 0
// and b >= 0
function poww($a, $b)
{
    if ($b == 0)
        return 1;
    $answer = $a;
    $increment = $a;
    $i;
    $j;
    for($i = 1; $i < $b; $i++)
    {
        for($j = 1; $j < $a; $j++)
        {
            $answer += $increment;
        }
        $increment = $answer;
    }
    return $answer;
}
 
    // Driver Code
    echo( poww(5, 3));
  
// This code is contributed by nitin mittal.
?>

Javascript




<script>
    /* Works only if a >= 0 and b >= 0 */
function pow(a , b)
{
    if (b == 0)
        return 1;
         
    var answer = a;
    var increment = a;
    var i, j;
     
    for (i = 1; i < b; i++)
    {
        for (j = 1; j < a; j++)
        {
            answer += increment;
        }
        increment = answer;
    }
     
    return answer;
}
 
// driver program to test above function
document.write(pow(5, 3));
 
// This code is contributed by shikhasingrajput
</script>

Output : 

125

Method 2 (Using Recursion) 
Recursively add a to get the multiplication of two numbers. And recursively multiply to get a raise to the power b.

C++




#include<bits/stdc++.h>
using namespace std;
 
/* A recursive function to get x*y */
int multiply(int x, int y)
{
    if(y)
        return (x + multiply(x, y - 1));
    else
        return 0;
}
 
/* A recursive function to get a^b
Works only if a >= 0 and b >= 0 */
int pow(int a, int b)
{
    if(b)
        return multiply(a, pow(a, b - 1));
    else
        return 1;
}
 
// Driver Code
int main()
{
    cout << pow(5, 3);
    getchar();
    return 0;
}
 
// This code is contributed
// by Akanksha Rai

C




#include<stdio.h>
/* A recursive function to get a^b
  Works only if a >= 0 and b >= 0  */
int pow(int a, int b)
{
   if(b)
     return multiply(a, pow(a, b-1));
   else
    return 1;
}   
 
/* A recursive function to get x*y */
int multiply(int x, int y)
{
   if(y)
     return (x + multiply(x, y-1));
   else
     return 0;
}
 
/* driver program to test above functions */
int main()
{
  printf("\n %d", pow(5, 3));
  getchar();
  return 0;
}

Java




import java.io.*;
 
class GFG {
     
    /* A recursive function to get a^b
    Works only if a >= 0 and b >= 0 */
    static int pow(int a, int b)
    {
         
        if (b > 0)
            return multiply(a, pow(a, b - 1));
        else
            return 1;
    }
 
    /* A recursive function to get x*y */
    static int multiply(int x, int y)
    {
         
        if (y > 0)
            return (x + multiply(x, y - 1));
        else
            return 0;
    }
 
    /* driver program to test above functions */
    public static void main(String[] args)
    {
        System.out.println(pow(5, 3));
    }
}
 
// This code is contributed by vt_m.

Python3




def pow(a,b):
     
    if(b):
        return multiply(a, pow(a, b-1));
    else:
        return 1;
      
# A recursive function to get x*y *
def multiply(x, y):
     
    if (y):
        return (x + multiply(x, y-1));
    else:
        return 0;
 
# driver program to test above functions *
print(pow(5, 3));
 
 
# This code is contributed
# by Sam007

C#




using System;
 
class GFG
{
    /* A recursive function to get a^b
    Works only if a >= 0 and b >= 0 */
    static int pow(int a, int b)
    {
         
        if (b > 0)
            return multiply(a, pow(a, b - 1));
        else
            return 1;
    }
 
    /* A recursive function to get x*y */
    static int multiply(int x, int y)
    {
         
        if (y > 0)
            return (x + multiply(x, y - 1));
        else
            return 0;
    }
 
    /* driver program to test above functions */
    public static void Main()
    {
        Console.Write(pow(5, 3));
    }
}
 
// This code is contributed by Sam007

PHP




<?php
 
/* A recursive function to get a^b
   Works only if a >= 0 and b >= 0 */
function p_ow( $a, $b)
{
    if($b)
        return multiply($a,
          p_ow($a, $b - 1));
    else
        return 1;
}
 
/* A recursive function
   to get x*y */
function multiply($x, $y)
{
    if($y)
        return ($x + multiply($x, $y - 1));
    else
        return 0;
}
 
// Driver Code
echo pow(5, 3);
 
// This code is contributed by anuj_67.
?>

Javascript




<script>
 
// A recursive function to get a^b
// Works only if a >= 0 and b >= 0
function pow(a, b)
{
    if (b > 0)
        return multiply(a, pow(a, b - 1));
    else
        return 1;
}
 
// A recursive function to get x*y
function multiply(x, y)
{
    if (y > 0)
        return (x + multiply(x, y - 1));
    else
        return 0;
}
 
// Driver code
document.write(pow(5, 3));
 
// This code is contributed by gauravrajput1
 
</script>

Output : 

125

 



Please write comments if you find any bug in above code/algorithm, or find other ways to solve the same problem.
 

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.  To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.

In case you wish to attend live classes with experts, please refer DSA Live Classes for Working Professionals and Competitive Programming Live for Students.




My Personal Notes arrow_drop_up
Recommended Articles
Page :