Java Program to Check if Two of Three Boolean Variables are True

Boolean values are true/false.  In this program, we need to check if any two out of three boolean values are true or not.

We will be discussing two major approaches to do it:

1. using an if-else.
2. using the ternary operator.

Approach 1: Using if-else condition

We initialize three boolean variable flags, with either a boolean FALSE or a TRUE value.

The counter approach can be used to check if two out of these three boolean variables are TRUE, by incrementing the counter value for each TRUE value. 

Java

// Java program to check if
// two out of three boolean
// variables are true

import java.io.*;

class GFG {
    public static void main(String[] args)
    {
        boolean flag1 = true;
        boolean flag2 = true;
        boolean flag3 = false;

        // maintaining a counter
        int cnt = 0;

        // check if flag1 is true, increment counter
        if (flag1)
            cnt += 1;

        // check if flag2 is true, increment counter
        if (flag2)
            cnt += 1;

        // check if flag3 is true, increment counter
        if (flag3)
            cnt += 1;

        // check counter value
        if (cnt == 2)

            System.out.println("Two flags are true!");

        else

            System.out.println("Two flags are not true!");
    }
}

Output

Two flags are true!

• Time Complexity: O(1)
• Space Complexity: O(1)

Another Method: Here, we will check if flag1 is true, then the ans should be true if either of flag2 or flag3 is true. Otherwise, if flag1 is false, then ans will be true when both flag2 and flag3 are true.

Java

// Java program to check
// if two out of three boolean
// variables are true

import java.io.*;

class GFG {
    public static void main(String[] args)
    {
        boolean flag1 = true;
        boolean flag2 = true;
        boolean flag3 = false;

        // to store the result
        boolean ans = false;

        if (flag1) {
           ans = flag2 || flag3;
        }
        else {
            ans = flag2 && flag3;
        }

        if (ans)
            System.out.println("Two flags are true!");
        else
            System.out.println("Two flags are not true!");
    }
}

Output

Two flags are true!

• Time Complexity: O(1)
• Space Complexity: O(1)

Approach 3: Using the ternary operator

Java

// Java program to check if
// two out of three boolean
// variables are true
import java.io.*;

class GFG {
    public static void main(String[] args)
    {
        boolean flag1 = true;
        boolean flag2 = true;
        boolean flag3 = true;

        // to store the result
        boolean ans = false;

        ans = flag1 ? flag2 || flag3 : flag2 && flag3;

        if (ans)
            System.out.println("Two flags are true!");
        else
            System.out.println("Two flags are not true!");
    }
}

Output

Two flags are not true!

• Time Complexity: O(1)
• Space Complexity: O(1)