What does while mean in c language?

The while loop is a C language control structure that allows a block of code to be executed repeatedly when a condition is met. Its usage includes: initializing condition variables. Test condition (true/false). Execute the code block (condition is true). Update the condition variable to decide whether to continue execution.

The meaning of while loop in C language

The while loop is a control structure that allows Repeat a block of code when conditional. The syntax of while loop is as follows:

<code class="c">while (condition) {
  // 代码块
}</code>

How to use while loop

1. Initialize condition variable: Before looping, you need to initialize a variable to store the value of the condition.
2. Test condition: The while loop starts with the condition in parentheses. The condition must be true or false.
3. Execute code block: If the condition is true, the code block within the brackets is executed.
4. Update condition variables: After the code block is executed, the value of the condition variable needs to be updated to decide whether to execute the code block again.

Application of while loop

While loop is widely used in the following scenarios in C language:

• Repetition Execution task: For example, print a string n times.
• Check input: The user can be prompted continuously before receiving valid input.
• Polling: Regularly check for changes in events or status.
• Game loop: Used to manage continuously updated scenes or game states.

Sample Code

The following code shows a while loop that calculates the sum from 1 to n:

<code class="c">#include <stdio.h>

int main() {
  int n;
  int sum = 0;

  // 提示用户输入 n
  printf("Enter a positive integer: ");
  scanf("%d", &n);

  // 初始化条件变量
  int i = 1;

  // 循环计算和
  while (i <= n) {
    sum += i;
    i++;
  }

  // 输出结果
  printf("The sum from 1 to %d is: %d\n", n, sum);

  return 0;
}</code>

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