Java Program to Calculate Power of a Number

🧾 Program 1: Using Math.pow() Function

// Java program to calculate power of a number using Math.pow()
import java.util.Scanner;

public class PowerCalculator {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        // Taking input from user
        System.out.print("Enter the base number: ");
        double base = sc.nextDouble();

        System.out.print("Enter the exponent: ");
        double exponent = sc.nextDouble();

        // Calculating power using Math.pow()
        double result = Math.pow(base, exponent);

        // Displaying the result
        System.out.println(base + " raised to the power " + exponent + " is: " + result);
    }
}

🧮 Example Output

Enter the base number: 2
Enter the exponent: 5
2.0 raised to the power 5.0 is: 32.0

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⚙️ Explanation

• Math.pow(base, exponent) is a built-in Java method that calculates base^exponent.

• It returns a double value.

• Example: Math.pow(2, 3) → 8.0

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🧾 Program 2: Using Loop (Without Math.pow())

// Java program to calculate power of a number without using Math.pow()
import java.util.Scanner;

public class PowerCalculatorLoop {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        System.out.print("Enter the base number: ");
        int base = sc.nextInt();

        System.out.print("Enter the exponent: ");
        int exponent = sc.nextInt();

        long result = 1;

        // Using for loop to calculate power
        for (int i = 1; i <= exponent; i++) {
            result *= base;
        }

        System.out.println(base + " raised to the power " + exponent + " is: " + result);
    }
}

🧮 Example Output

Enter the base number: 3
Enter the exponent: 4
3 raised to the power 4 is: 81

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🧠 Explanation

• This program multiplies the base number repeatedly.

• If exponent = 4 and base = 3 →
  3 × 3 × 3 × 3 = 81

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🧩 Program 3: Using Recursion

// Java program to calculate power using recursion
import java.util.Scanner;

public class PowerRecursion {
    static long power(int base, int exponent) {
        if (exponent == 0)
            return 1;
        else
            return base * power(base, exponent - 1);
    }

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        System.out.print("Enter the base number: ");
        int base = sc.nextInt();

        System.out.print("Enter the exponent: ");
        int exponent = sc.nextInt();

        long result = power(base, exponent);
        System.out.println(base + " raised to the power " + exponent + " is: " + result);
    }
}

🧮 Example Output

Enter the base number: 5
Enter the exponent: 3
5 raised to the power 3 is: 125

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🏁 Conclusion

• ✅ Use Math.pow() for quick calculations.

• ✅ Use a loop if you want to understand how powers work internally.

• ✅ Use recursion for practicing function calls.