Question

Write a java program to convert a decimal number to binary number. Provide the Big O analysis

Answer 1

//TestCode.java
import java.util.Scanner;
public class TestCode {
  public static String dec2Bin(int value) {
    if (value == 0) {
      return "";
    } else {
      return dec2Bin(value / 2) + "" + (value % 2);
    }
  }

  public static void main(String args[]) {
    int num;
    Scanner sc = new Scanner(System.in);
    System.out.print("Enter decimal number: ");
    num = sc.nextInt();
    System.out.println(dec2Bin(num));
  }
}

$\color{blue}\underline{Time \;complexity\;:}$

Time complexity = =O(Number of digits in the resultant binary)