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Control flow statements in Java

Control flow statements in Java are used to manage the flow of execution in a program. They determine the order in which statements are executed based on certain conditions. Here are the main control flow statements in Java:


1. if Statement:

   - The `if` statement is used for conditional branching.

   - It executes a block of code if a specified condition is true.


   int x = 10;

   if (x > 5) {

       // code to execute if x is greater than 5

   }



2. if-else Statement:

   - The `if-else` statement allows branching based on a condition.

   - It executes one block of code if the condition is true and another if it's false.


   int x = 10;

   if (x > 5) {

       // code to execute if x is greater than 5

   } else {

       // code to execute if x is not greater than 5

   }



3. if-else if-else Statement:

   - This structure allows handling multiple conditions sequentially.



   int x = 10;

   if (x > 5) {

       // code to execute if x is greater than 5

   } else if (x < 5) {

       // code to execute if x is less than 5

   } else {

       // code to execute if x is equal to 5

   }



4. Switch Statement:

   - The `switch` statement is used for multiple branching based on the value of an expression.

   - It replaces multiple `if-else if` statements for readability.


   int day = 3;

   switch (day) {

       case 1:

           // code for Monday

           break;

       case 2:

           // code for Tuesday

           break;

       // other cases...

       default:

           // code for other days

   }

   


5. while Loop:

   - The `while` loop repeatedly executes a block of code while a specified condition is true.


  

   int i = 0;

   while (i < 5) {

       // code to execute while i is less than 5

       i++;

   }



6. do-while Loop:

   - The `do-while` loop is similar to `while`, but it ensures the block of code is executed at least once.


   int i = 0;

   do {

       // code to execute (at least once)

       i++;

   } while (i < 5);



7. for Loop:

   - The `for` loop is used for iterating over a range of values.


   for (int i = 0; i < 5; i++) {

       // code to execute for each iteration

   }



8. break and continue Statements:

   - `break` is used to exit a loop prematurely, and `continue` is used to skip the rest of the code in a loop and move to the next iteration.


   for (int i = 0; i < 10; i++) {

       if (i == 5) {

           break; // exit the loop when i is 5

       }

       if (i % 2 == 0) {

           continue; // skip even numbers

       }

       // code to execute for odd numbers

   }



Control flow statements are essential for building logic and making decisions in Java programs. They provide the necessary tools for creating structured and efficient code.

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