Hello Programmers, In this post, you will know how to solve the Java Lambda Expressions HackerRank Solution. This problem is a part of the HackerRank Java Programming Series.
One more thing to add, don’t directly look for the solutions, first try to solve the problems of Hackerrank by yourself. If you find any difficulty after trying several times, then you can look for solutions.
Java Lambda Expressions HackerRank Solution
Objective
This Java 8 challenge tests your knowledge of Lambda expressions!
Write the following methods that return a lambda expression performing a specified action:
- PerformOperation isOdd(): The lambda expression must return True if a number is odd or False if it is even.
- PerformOperation isPrime(): The lambda expression must return True if a number is prime or False if it is composite.
- PerformOperation isPalindrome(): The lambda expression must return True if a number is a palindrome or False if it is not.
Input Format
Input is handled for you by the locked stub code in your editor.
Output Format
The locked stub code in your editor will print lines of output.
Sample Input
The first line contains an integer, (the number of test cases).
The subsequent lines each describe a test case in the form of space-separated integers:
The first integer specifies the condition to check for ( for Odd/Even, for Prime, or for Palindrome). The second integer denotes the number to be checked.
5
1 4
2 5
3 898
1 3
2 12
Sample Output
EVEN
PRIME
PALINDROME
ODD
COMPOSITEJava Lambda Expressions HackerRank Solutions
import java.io.*;
import java.util.*;
interface PerformOperation {
boolean check(int a);
}
class MyMath {
public static boolean checker(PerformOperation p, int num) {
return p.check(num);
}
PerformOperation isOdd()
{
PerformOperation po = (int a)-> a%2 == 0 ? false : true;
return po;
}
PerformOperation isPrime()
{
PerformOperation po = (int a)->
{
if(a == 1) return true;
else
{
for (int i = 2; i < Math.sqrt(a); i++)
if(a%i == 0) return false;
return true;
}
};
return po;
}
PerformOperation isPalindrome()
{
ArrayList<Integer> aa = new ArrayList<>();
PerformOperation po = (int a)->
{
String str = Integer.toString(a);
String reverse = "";
for(int i = str.length()-1; i >= 0; i--)
{
reverse = reverse + str.charAt(i);
}
if(reverse.equals(str)) return true;
return false;
};
return po;
}
}
public class Solution {
public static void main(String[] args) throws IOException {
MyMath ob = new MyMath();
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
int T = Integer.parseInt(br.readLine());
PerformOperation op;
boolean ret = false;
String ans = null;
while (T--> 0) {
String s = br.readLine().trim();
StringTokenizer st = new StringTokenizer(s);
int ch = Integer.parseInt(st.nextToken());
int num = Integer.parseInt(st.nextToken());
if (ch == 1) {
op = ob.isOdd();
ret = ob.checker(op, num);
ans = (ret) ? "ODD" : "EVEN";
} else if (ch == 2) {
op = ob.isPrime();
ret = ob.checker(op, num);
ans = (ret) ? "PRIME" : "COMPOSITE";
} else if (ch == 3) {
op = ob.isPalindrome();
ret = ob.checker(op, num);
ans = (ret) ? "PALINDROME" : "NOT PALINDROME";
}
System.out.println(ans);
}
}
}Disclaimer: The above Problem (Java Lambda Expressions) is generated by Hackerrank but the Solution is Provided by BrokenProgrammers. This tutorial is only for Educational and Learning purposes.