Interview Programs Archives

LRU Cache

In today’s computing world, efficiency is key. One of the critical components that can make your application more efficient is caching. Among various caching strategies, the Least Recently Used (LRU) cache is a popular one. In this blog, we’ll delve into what an LRU cache is, why it is useful, and how you can implement … Continue reading “LRU Cache”

Anagram In Java

Any word or phrase that exactly reproduces the letters in another order is an anagram. Example: cat – act, study – dusty, gainly – laying etc., Logic for anagram is below:

import java.util.Arrays;

public class Anagram {

	public static void main(String[] args) {
		
		System.out.println(" Is cat,act Anagram: " + isAnagram("cat", "act"));
		System.out.println(" Is study,dusty Anagram: " + isAnagram("study", "dusty"));
		System.out.println(" Is gainly,laying Anagram: " + isAnagram("gainly", "laying"));
	}
	
	public static boolean isAnagram(String inputStr1, String inputStr2) {
		
		if(inputStr1==null || inputStr2 == null || (inputStr1.length()!=inputStr2.length())) {
			return false;
		}
		
		char[] letters1 = inputStr1.toUpperCase().toCharArray();
		char[] letters2 = inputStr2.toUpperCase().toCharArray();
		Arrays.sort(letters1);
		Arrays.sort(letters2);
		
		return Arrays.equals(letters1, letters2);
		
	}
}

import java.util.Arrays;

public class Anagram {

public static void main(String[] args) {

System.out.println(" Is cat,act Anagram: " + isAnagram("cat", "act"));

System.out.println(" Is study,dusty Anagram: " + isAnagram("study", "dusty"));

System.out.println(" Is gainly,laying Anagram: " + isAnagram("gainly", "laying"));

}

public static boolean isAnagram(String inputStr1, String inputStr2) {

if(inputStr1==null || inputStr2 == null || (inputStr1.length()!=inputStr2.length())) {

return false;

}

char[] letters1 = inputStr1.toUpperCase().toCharArray();

char[] letters2 = inputStr2.toUpperCase().toCharArray();

Arrays.sort(letters1);

Arrays.sort(letters2);

return Arrays.equals(letters1, letters2);

}

Output:

Armstrong Number In Java

Armstrong Number is a number that is the sum of its own digits each raised to the power of the number of digits. Example: 13+53+33=153 which is same as given number 153., and 3 is the number of digits. 14+64+34+44=1634 which is same as given number 1634., and 4 is the number of digits.

package my.test;

public class ArmstrongNumber {

	public static void main(String[] args) {
		
		System.out.println("Is 153 ArmsStrong Number: " + isArmstrongNumber(153));
		System.out.println("Is 1634 ArmsStrong Number: " + isArmstrongNumber(1634));
		System.out.println("Is 93084 ArmsStrong Number: " + isArmstrongNumber(93084));
		System.out.println("Is 9800817 ArmsStrong Number: " + isArmstrongNumber(9800817));
		System.out.println("Is 407 ArmsStrong Number: " + isArmstrongNumber(407));
		System.out.println("Is 406 ArmsStrong Number: " + isArmstrongNumber(406));
	}
	
	public static boolean isArmstrongNumber(int number) {
		if(number>0) {
			// Find number of digits in the given number..
			int temp = number;
			int numberOfDigits = 0;
			while(temp>0) {
				temp =temp/10;
				numberOfDigits++;
			}
			//Power each digits with the number of digits..
			int temp2 = number;
			int calcNumber = 0;
			while(temp2>0) {
				calcNumber = (int) (calcNumber + Math.pow((temp2%10), numberOfDigits));
				temp2 = temp2/10;
			}
			if(calcNumber == number) {
				return true;
			}
		}
		return false;
	}
}

package my.test;

public class ArmstrongNumber {

public static void main(String[] args) {

System.out.println("Is 153 ArmsStrong Number: " + isArmstrongNumber(153));

System.out.println("Is 1634 ArmsStrong Number: " + isArmstrongNumber(1634));

System.out.println("Is 93084 ArmsStrong Number: " + isArmstrongNumber(93084));

System.out.println("Is 9800817 ArmsStrong Number: " + isArmstrongNumber(9800817));

System.out.println("Is 407 ArmsStrong Number: " + isArmstrongNumber(407));

System.out.println("Is 406 ArmsStrong Number: " + isArmstrongNumber(406));

}

public static boolean isArmstrongNumber(int number) {

if(number>0) {

// Find number of digits in the given number..

int temp = number;

int numberOfDigits = 0;

while(temp>0) {

temp =temp/10;

numberOfDigits++;

}

//Power each digits with the number of digits..

int temp2 = number;

int calcNumber = 0;

while(temp2>0) {

calcNumber = (int) (calcNumber + Math.pow((temp2%10), numberOfDigits));

temp2 = temp2/10;

}

if(calcNumber == number) {

return true;

}

return false;

}

… Continue reading “Armstrong Number In Java“

Palindrome String In Java

What is Palindrome? A Palidrome string is a string where if we reverse the string, the word will be same. A palindrome is a word, number, phrase, or other sequence of characters which reads the same backward as forward. Example: madam, refer, redivider The logic in Java for implementation is very simple.,

package my.test;
public class Palindrome {
	public static void main(String[] args) {
		String string1 = "abcdcba";
		String string2 = "abcde";
		String string3 = "madam";
		String string4 = "refer";
		String string5 = "hello";
		
		System.out.println("Is String 1 Palindrome : " + isPalindrome(string1));
		System.out.println("Is String 2 Palindrome : " + isPalindrome(string2));
		System.out.println("Is String 3 Palindrome : " + isPalindrome(string3));
		System.out.println("Is String 4 Palindrome : " + isPalindrome(string4));
		System.out.println("Is String 5 Palindrome : " + isPalindrome(string5));
	}
	public static boolean isPalindrome(String str) {
		String reverseString = "";
		if(str!=null && str.length()>0) {
			char[] charArray = str.toCharArray();
			for(int i=charArray.length-1;i&gt;=0;i--){
				reverseString = reverseString + charArray&#91;i];
			}
		}else {
			return false;
		}
		System.out.println("Input String: " + str + " , Reversed String: " +reverseString);
		if(str.equalsIgnoreCase(reverseString)) {
			return true;
		}
		else{
			return false;
		}
	}
}

package my.test;

public class Palindrome {

public static void main(String[] args) {

String string1 = "abcdcba";

String string2 = "abcde";

String string3 = "madam";

String string4 = "refer";

String string5 = "hello";

System.out.println("Is String 1 Palindrome : " + isPalindrome(string1));

System.out.println("Is String 2 Palindrome : " + isPalindrome(string2));

System.out.println("Is String 3 Palindrome : " + isPalindrome(string3));

System.out.println("Is String 4 Palindrome : " + isPalindrome(string4));

System.out.println("Is String 5 Palindrome : " + isPalindrome(string5));

}

public static boolean isPalindrome(String str) {

String reverseString = "";

if(str!=null && str.length()>0) {

char[] charArray = str.toCharArray();

for(int i=charArray.length-1;i>=0;i--){

reverseString = reverseString + charArray[i];

}

}else {

return false;

}

System.out.println("Input String: " + str + " , Reversed String: " +reverseString);

if(str.equalsIgnoreCase(reverseString)) {

return true;

}

else{

return false;

}

Output: Input String: abcdcba … Continue reading “Palindrome String In Java“

Fibonacci series

Fibonacci Series is one of the basic questions in Java., to check the programmer has a basic understanding of logic implementation in java.In Fibonacci series, the current number is always the sum of previous two numbers.Fibonacci series is initialized with 0 & 1.0, 1, (0+1)2, (1+2)3, (2+3)5, (3+5)8, (5+8)13….

public class Fibonocci {

	public static void main(String args[]) {

		int previousNumber = 0;
		int recentNumber   = 1;
		
		int nextNumber;
		int count = 20;
		System.out.print(previousNumber + " " + recentNumber);

		for (int i = 2; i < count; ++i)
		
			nextNumber = previousNumber + recentNumber;
			System.out.print(" " + nextNumber);

			previousNumber = recentNumber;
			recentNumber = nextNumber;
		}
	}
}

public class Fibonocci {

public static void main(String args[]) {

int previousNumber = 0;

int recentNumber = 1;

int nextNumber;

int count = 20;

System.out.print(previousNumber + " " + recentNumber);

for (int i = 2; i < count; ++i)

nextNumber = previousNumber + recentNumber;

System.out.print(" " + nextNumber);

previousNumber = recentNumber;

recentNumber = nextNumber;

}

Output 0 1 1 2 … Continue reading “Fibonacci series“