The method pow(long b, int k) of Guava’s LongMath Class returns b to the kth power. Even if the result overflows, it will be equal to BigInteger.valueOf(b).pow(k).longValue(). This implementation runs in O(log k) time.
Syntax:
public static long pow(long b, int k)
Parameters: The method accepts two parameters, b and k. The parameter b is called base which is raised to the k-th power.
Return Value: This method returns the k-th power of b.
Exception: This method throws IllegalArgumentException if k is negative.
Example 1:
// Java code to show implementation of // pow(long b, int k) method of Guava's // LongMath Class import java.math.RoundingMode; import com.google.common.math.LongMath; class GFG { // Driver code public static void main(String args[]) { long b1 = 4 ; int k1 = 5 ; long ans1 = LongMath.pow(b1, k1); System.out.println(b1 + " to the " + k1 + "th power is: " + ans1); long b2 = 12 ; int k2 = 3 ; long ans2 = LongMath.pow(b2, k2); System.out.println(b2 + " to the " + k2 + "rd power is: " + ans2); } } |
4 to the 5th power is: 1024 12 to the 3rd power is: 1728
Example 2:
// Java code to show implementation of // pow(long b, int k) method of Guava's // LongMath class import java.math.RoundingMode; import com.google.common.math.LongMath; class GFG { static long findPow( long b, int k) { try { // Using pow(long b, int k) // method of Guava's LongMath class // This should throw "IllegalArgumentException" // as k < 0 long ans = LongMath.pow(b, k); // Return the answer return ans; } catch (Exception e) { System.out.println(e); return - 1 ; } } // Driver code public static void main(String args[]) { long b = 4 ; int k = - 5 ; try { // Using pow(long b, int k) // method of Guava's LongMath class // This should throw "IllegalArgumentException" // as k < 0 LongMath.pow(b, k); } catch (Exception e) { System.out.println(e); } } } |
java.lang.IllegalArgumentException: exponent (-5) must be >= 0