How to use while loop in java

The while loop in Java is used to repeatedly execute a block of code when a condition is true. Usage includes: initialize condition, check condition, execute code block, update state, repeat steps 2-4 until condition becomes false. For example, to print numbers from 1 to 10 you can use a while loop: int i = 1; while (i <= 10) { System.out.println(i); i ; }

Usage of while loop in Java

The while loop is a control flow statement in Java that is used to execute a block of code when a given condition is true. The syntax is as follows:

<code>while (condition) {
  // 代码块
}</code>

where:

• condition is a Boolean expression that evaluates the condition.
• Code block is the code to be executed.

Usage:

1. Initialization: Before using a while loop, you usually need to initialize the loop variables or conditions.
2. Condition checking: The program will check whether the condition is true.
3. Code execution: If the condition is true, the code block will be executed.
4. Loop update: After executing a block of code, it is often necessary to update loop variables or other state to ensure that the condition is still true on the next iteration.
5. Repeat steps 2-4: Continue checking the condition and executing the code block until the condition becomes false.

Example:

Print numbers from 1 to 10:

int i = 1;
while (i <= 10) {
  System.out.println(i);
  i++;
}

Points to note:

• The while loop will continue to execute until the condition becomes false, so you must ensure that the loop will eventually terminate.
• If the condition is always true, the program will enter an infinite loop, causing the program to crash.
• You can use the break statement to force out of the loop.
• You can use the continue statement to skip the remainder of the current loop iteration.

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