# Calculate Power of Integers in Java

Rupam Yadav Jan 30, 2023 Mar 15, 2021

In this tutorial, we will look into various approaches to calculate the power of an integer. There are standard methods for this purpose. It can also be achieved using a loop as well as the Java library function.

## Use the `for` Loop to Calculate the Power of an Integer in Java

The power of a number is the number of times a number is to be multiplied by itself. We calculate the power of a number using a `for` loop as given below. Here we have variables, `num` and `power` of data type `int`.

The function `calculatePower(int num, int power)` has three conditions. First, if the number is greater than 0 but the power is 0 it will return 1. If the power is not 0, but the number is 0, then 0 is returned.

In the other case, we run a loop that calculates the given number’s exponent raised to the given power.

``````public class Power {
public static void main(String args[]){
int number = 5;
int power = 3;
int result = calculatePower(number,power);
System.out.println(number+"^"+power+"="+result);
}
static int calculatePower(int num, int power){
if(num > 0 && power==0){
}
else if(num == 0 && power>=1){
return 0;
}
else{
for(int i = 1; i<= power; i++){
}
}
}
}
``````

Output:

``````5^3=125
``````

## Use Recursion to Calculate the Power of an Integer in Java

We can use the recursive function `CalculatePower` to calculate the power of an integer. A Recursion is a mechanism that helps a function call itself.

Here the recursive call to the `CalculatePower` function continues until the stop condition meets, which is if `pow` we passed is equal to 0.

``````public class Power {
public static void main(String args[]){
int number = 3;
int power = 3;
int result = CalculatePower(number,power);
System.out.println(number+"^"+power+"="+result);
}
static int CalculatePower (int num, int pow){
if (pow == 0)
return 1;
else
return num * CalculatePower(num, pow - 1);
}
}
``````

Output:

``````3^3=27
``````

## Use `Math.pow()` to Calculate the Power of an Integer in Java

We can easily calculate the power of an integer with the function `Math.pow()` provided by the Java library. The number raised to the power of some other number can be calculated using this function.

This method takes two parameters; the first number is the base while the second is the exponent. If the pass exponent is 0, then the returned result will be 1, while the result will be the base value only if the exponent is 1. If the second parameter passed is `NaN`, then the result will also be `NaN`.

``````import java.lang.Math;
public class Power {
public static void main(String args[]){
int number = 6;
int power = 3;
double result = CalculatePower(number,power);
System.out.println(number+"^"+power+"="+result);
}
static double CalculatePower (int num, int pow){
return Math.pow(num,pow);
}
}
``````

Output:

``````6^3=216.0
``````