Addition of two given numbers-CodePudding

Basically is about the binary numbers, the user needs to input two random numbers, both numbers will be added, and the addition of those two numbers only needs to have ones and zeros for example 5 6==11 OR 55 55=110, then throw a message saying “the addition only has 1’s and 0’s, otherwise for example 25 46=71 or 575 575=1150 then a message saying the addition does not have only 1’s and 0’s.

I just started learning java and i can’t find anything helpful for this problem, i already know the conditionals if only have ones and zeros or not.

this is the code i already have, but when i input for example 575 575 1150 says only has 1's and 0's, i guess i cant use .contains for this.

public static void main(String[] args) {
    Scanner read = new Scanner(System.in);
    int n1;
    int n2;
    int add;
    
    System.out.print("Input Number 1: ");
    n1=read.nextInt();
    System.out.print("Input number 2: ");
    n2=read.nextInt();
    System.out.println();
    add=n1 n2;
    System.out.println("The addition is =  " add); 
    
    String S = String.valueOf(add);
    
    if(S.contains("1") && S.contains("0")) {
     System.out.print("The addition only has 1's and 0's");
    }
    else{System.out.print("The addition does not only have 1's and 0's");}
        
}

}

CodePudding user response：

I saw your code and and the resultant sum 1150 does contain 1's and 0's.

s.contains(x);

This function only checks if the string contains the value x or not. Since "1150" contains both 1's and 0's therefore your function prints the wrong output.

One way of solving this problem would be to add the two numbers and then check the resultant sum digit by digit. You can make a function that will do that for you.

public void checkOnesAndZeros(int resultantSum) {
        while (resultantSum > 0) {
            int remainder = resultantSum % 10;
            if(remainder != 1 && remainder != 0) {
                System.out.println("The addition does not have only 1’s and 0’s.");
                return;
            }
            resultantSum = resultantSum / 10;
        }
        System.out.println("The addition only has 1’s and 0’s");
    }

CodePudding user response：

One way is to create a String using the added numbers and iterating through the characters.

public static boolean isResultBinary(int n1, int n2) {
    String sum = n1   n2   "";
    for (int i = 0; i < sum.length(); i  ) {
        char c = sum.charAt(i);
        if (c != '1' && c != '0') return false;
    }
    return true;
}

Here's a method I wrote, it checks every character c to see if it is either '0' and '1'. If a character is not either one, the method will return false. Otherwise, it'll loop through the whole string and return true.

To get your desired output, use this method like this in within your main method:

if (isResultBinary(n1, n2)) System.out.println("The addition only has 1's and 0's");
else System.out.print("The addition does not only have 1's and 0's");

CodePudding user response：

Here is another take on the question.

convert the sum to a string and then try and parse it as binary.
if it isn't binary, an exception will be thrown, so return false.
otherwise return true.

int[] sums = { 110, 120, 10111, 250, 203, 2011, 1110111 };
for (int n : sums) {
    System.out.printf("%8s - %s%n", n,
            "is "   (checkOnesAndZeros(n) ? "" : "not ")
                      "all ones and zeros");
}

prints

     110 - is all ones and zeros
     120 - is not all ones and zeros
   10111 - is all ones and zeros
     250 - is not all ones and zeros
     203 - is not all ones and zeros
    2011 - is not all ones and zeros
 1110111 - is all ones and zeros

The method

public static boolean checkOnesAndZeros(int resultantSum) {
    try {
        Integer.parseInt(Integer.toString(resultantSum), 2);
        return true;
    } catch (NumberFormatException nfe) {
        return false;
    }
}