Coding an exclusive OR program by creating a truth chart.

[silver berry]

I'm not sure how to code this into my program... I've been thinking about using a loop and printing the values but I'm not sure how I would hit every condition (especially the False False Condition).

[old depot]

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TIP: Narrow down your issue to simple and precise questions to maximize the chance that others will reply in here.

[silver berry]

public class PXORQ {
  public static void main (String [] args) {
    boolean P = true; 
    boolean Q = true; 
    System.out.format("%s\t\t%s\t\t%s", "p", "q", "(p xor q)"); 
    System.out.println("--------------------------------");
    
    for (int i = 0; i < 4; i++) {
      if ((P || Q) && (P && Q)) {
        System.out.format("%16s", "false"); 
        Q = !Q; 
      }
      else if ((P || Q) == false) {
        System.out.format("16s", "false"); 
      }
      else if ((P || Q) == true) {
        System.out.format("%16s", "true"); 
        P = !P; 
        Q = !Q; 
      }
     
    }
  }
}```

This is what I have rn

[covert phoenix]

could just hardcode the 4 cases

[silver berry]

Like

ohhh

[covert phoenix]

that would be much easier

[silver berry]

I don't really need a loop do I

[covert phoenix]

yeah

[silver berry]

I'll try that right now

[covert phoenix]

have a separate method that does the XOR, then just do System.out.format(..., true, true, xor(true, true)); or something like that

or you could have the print in the method for guaranteed consistency as well

(sidenote, xor can be done with just !=, although this task seems like it wants you to use the full form)

[silver berry]

xor can be done with !=?

hmm

oh yea

that makes a lot of sense

yea I think the teacher wants me to do it manually...

  public static void main (String [] args) {
    boolean P = true; 
    boolean Q = true; 
    System.out.format("%s\t\t%s\t\t%s\n", "p", "q", "(p xor q)"); 
    System.out.println("--------------------------------");
  
    if ((P || Q) && (P && Q)) {
      System.out.format("%s%8s%16s\n", "true", "true", "false"); 
    }

    Q = false;
    if ((P || Q) == true) {
      System.out.format("%s%8s%16s\n", "true", "false", "true"); 
    }

    P = true;
    Q = false; 
    if ((P || Q) == true) {
      System.out.format("%s%8s%16s\n", "false", "true", "true"); 
    }

    P = false;
    if ((P || Q) == false) {
      System.out.format("%s%8s%16s\n", "false", "false", "false"); 
    }
    
  }
}```

oh

public class PXORQ {
  public static void main (String [] args) {
    boolean P = true; 
    boolean Q = true; 
    System.out.format("%s\t\t%s\t\t%s\n", "p", "q", "(p xor q)"); 
    System.out.println("--------------------------------");
  
    if ((P || Q) && (P && Q)) {
      System.out.format("%s%8s%16s\n", "true", "true", "false"); 
    }

    Q = false;
    if ((P || Q) == true) {
      System.out.format("%s%8s%16s\n", "true", "false", "true"); 
    }

    P = true;
    Q = false; 
    if ((P || Q) == true) {
      System.out.format("%s%8s%16s\n", "false", "true", "true"); 
    }

    P = false;
    if ((P || Q) == false) {
      System.out.format("%s%8s%16s\n", "false", "false", "false"); 
    }
    
  }
}```

Some weird formatting errors...

[covert phoenix]

make a separate method, it'll make it much easier to work with

also that isn't exactly doing XOR

[silver berry]

is it not?

[covert phoenix]

no, you're hardcoding the results as well

you need to only hardcode the inputs here

[silver berry]

ah

oh right

Ok ok

let's create a method

[covert phoenix]

also you could use %b with booleans directly instead of %s and stringified booleans

[silver berry]

Oh

great point

wooo

public class PXORQ {

  public static boolean exclusiveOr (boolean case1, boolean case2) {
    if ((case1 || case2) && (case1 && case2)) {
      return false; 
    }
    else if (case1 || case2) {
      return true; 
    }
    else {
      return false; 
    }
  }
  
  public static void main (String [] args) {
    boolean P = true; 
    boolean Q = true; 
    System.out.format("%s\t\t%s\t\t%s\n", "p", "q", "(p xor q)"); 
    System.out.println("--------------------------------");
    System.out.format("%b%8b%16b\n", true, true, exclusiveOr(true, true)); 
    System.out.format("%b%8b%16b\n", true, false, exclusiveOr(true, false)); 
    System.out.format("%b%8b%16b\n", false, true, exclusiveOr(false, true)); 
    System.out.format("%b%8b%16b\n", false, false, exclusiveOr(false, false)); 
  

  }
}```

formatting is scuffed

I'll fix that

👯‍♂️

oops

🥳

!clse

!lose

!close