Java find output programs (if else) | set 1

Find the output of Java programs | if else | Set 1: Enhance the knowledge of Java if else concepts by solving and finding the output of some Java programs.
Submitted by Nidhi, on January 30, 2021

Question 1:

public class Main {
  public static void main(String[] args) {
    int num = 101;

    if (num = 101) {
      System.out.println("Hello");
    }
    else {
      System.out.println("Hiiii");
    }
  }
}

Output:

Main.java:5: error: incompatible types: int cannot be converted to boolean
    if (num = 101) {
            ^
1 error

Explanation:

The above program will generate a syntax error because the if condition in Java required boolean value. In the if condition, we assign variable num with 101. The condition will be:

if(101)

We cannot use integer value for conditions in Java.

Question 2:

public class Main {
  public static void main(String[] args) {
    int A = 10;
    int B = 20;
    int C = 30;

    C = ++A * --B + C;

    if (A == (++B * 2)) {
      System.out.println("Hello: " + C);
    }
    else {
      System.out.println("Hiii: " + C);
    }
  }
}

Output:

Hiii: 239

Explanation:

In the above program, we created a class Main that contains a main() method, the main() method is the entry point of the program, here we declared three integer variables A, B, and C initialized with 10, 20, 30.

Now evaluate the expression:

C = ++A * --B + C;

First, evaluate ++A, then A becomes 11, and then evaluate --B, then B becomes 19.

C = A *B + C; 
C = 11*19+30;
C = 209+30
C = 239

Let's check the condition given below,

if (A==(++B*2))
if (A==(20*2))
if (A==400)

A contains 11 then the if condition will false that's why "Hiii: 239" will be printed on the console screen.

Question 3:

public class Main {
  public static void main(String[] args) {
    float A = 2.34F;
    double B = 2.34;

    if (A == B) {
      System.out.println("www.includehelp.com");
    }
    else {
      System.out.println("www.google.com");
    }
  }
}

Output:

www.google.com

Explanation:

In the above program, we created a class Main that contains a main() method, the main() method is the entry point of the program, here we declared two variables A and B that are initialized with "2.34F" and "2.34" respectively.

Here, A is float type, and B is double type then both numbers will not equal then condition get false and www.google.com will print on the console screen.

Question 4:

public class Main {
  public static void main(String[] args) {
    int A = -2;

    if (A > null) {
      System.out.println("www.includehelp.com");
    }
    else {
      System.out.println("www.google.com");
    }
  }
}

Output:

Main.java:5: error: bad operand types for binary operator '>'
    if (A > null) {
          ^
  first type:  int
  second type: <null>
1 error

Explanation:

The above program will generate a syntax error because we cannot compare the integer variable with null.

Question 5:

public class Main {
  public static void main(String[] args) {
    int NUM = 0;
    String STR = "Hello World";

    NUM = STR.length();

    if (NUM % 2 == 0) {
      System.out.println("NUM is EVEN number");
    }
    else {
      System.out.println("NUM is ODD number");
    }
  }
}

Output:

NUM is ODD number

Explanation:

In the above program, we created a class Main that contains a main() method, the main() method is the entry point of the program, here we declared two variables NUM and STR that are initialized with 0 and "Hello World" respectively.