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How to convert binary number to decimal in C# using method.

using System;

    class BinToDec
    {
        static void Main(string[] args)
        {
            string binary = "101";
            Console.WriteLine(BinaryToDecimal(binary)); // will return 5

        }

        private static long BinaryToDecimal(string binary)
        {
            long decimalNum = 0;
            for (int i = binary.Length - 1, pow = 0; i >= 0; i--, pow++)
            {
                decimalNum += int.Parse(binary[i].ToString()) * (long)Math.Pow(2, pow);
            }

            return decimalNum;
        }
    }

How to print list separated by comma in Java

import java.util.ArrayList;
import java.util.stream.Collectors;

public class CommaDelimeter {
    public static void main(String[] args) {
        ArrayList<Integer> collectNums = new ArrayList<Integer>();
        collectNums.add(2);
        collectNums.add(9);
        collectNums.add(12);

        String joined = collectNums.stream()
                .map(Object::toString)
                .collect(Collectors.joining(", "));

        System.out.println(joined);
    }
}

How to generate all subsets of power set using bitwise mask in C#

namespace SubsetsOfSet
{
    using System;
    using System.Collections.Generic;
    using System.Linq;

    class SubsetsOfSet
    {
        static void Main()
        {
            int[] nums = { 0, 1, 2 };
            string[] fruits = {"apple", "peach", "starwberry"};

            int b = nums.Length;
            int n = (int)Math.Pow(2, b);

            for (int num = 0; num < n; num++)
            {
                var subSet = new List<int>();
                for (int bit = 0; bit <= b; bit++)
                {
                    if ((num >> bit & 1) == 1)
                    {
                        subSet.Add(nums[bit]);
                    }
                }

                Console.WriteLine("{{{0}}}", string.Join(", ", subSet.Select(i => fruits[i])));
            }
        }
    }
}

How to generate random integer in range in Java

import java.util.Random;

public class RandomNumInRange {
    public static void main(String[] args) {
        int min = 10;
        int max = 20;

        Random rand = new Random();
        int randNum = rand.nextInt((max - min) + 1) + min;
        System.out.print(randNum);
    }
}

How to split by forward or/and back slash in Java using RegEx

public class MatchBackslashRegex {
    public static void main(String[] args) {
        String string = "Element1\\Element2";
        String[] strArr = string.split("/\\\\");
        System.out.println(strArr[0]); // returns Element1
    }
}

How to reverse String in Java

public class ReverseString {
    public static void main(String[] args) {
        String a = "Test";
        String aReversed = new StringBuilder(a).reverse().toString();
        System.out.println(aReversed); // returns tseT
    }
}