2018-10-12 20:35:31 +00:00
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---
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2018-10-19 12:53:51 +00:00
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title: While-loop
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2018-10-12 20:35:31 +00:00
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localeTitle: undefined
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---
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只要给定条件为真,while循环语句就会重复执行目标语句。
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句法: while(condition){ 声明(S); }
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while循环的一个关键点是循环可能永远不会运行。 当测试条件并且结果为假时,将跳过循环体并且将执行while循环之后的第一个语句。
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例:
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```C++
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2018-10-19 12:53:51 +00:00
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#include <iostream>
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using namespace std;
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int main () {
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// Local variable declaration:
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int a = 10;
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// while loop execution
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while( a < 20 ) {
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cout << "value of a: " << a << endl;
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a++;
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}
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return 0;
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}
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2018-10-12 20:35:31 +00:00
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```
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输出:
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价值:10 价值:11 价值:12 价值a:13 a的值:14 价值a:15 价值:16 价值:17 价值:18 价值:19
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### 来源
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www.tutorialspoint.com
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