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while loop

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C++
 
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流量控制
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条件执行语句
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while loop
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执行一个循环.....
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Executes a loop.
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使用代码需要多次执行，而一些条件是.
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目录

[编辑] 语法

while ( cond_expression ) loop_statement

[编辑] 解释

cond_expression应该是一个表达式，其结果是转换为bool。 loop_statement，如果只执行cond_expression评估true每次执行前评估.
Original:
cond_expression shall be an expression, whose result is convertible to bool. It is evaluated before each execution of loop_statement, which is only executed if the cond_expression evaluates to true.
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如果循环执行的，在某些时候，需要终止，<div class="t-tr-text"> break语句
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break statement
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​​可以用作终止声明.
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If the execution of the loop needs to be terminated at some point,
break语句
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break statement
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</div> can be used as terminating statement.
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如果需要继续执行循环在循环体的末尾，<div class="t-tr-text"> continue语句
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continue statement
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可以用作快捷.
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If the execution of the loop needs to be continued at the end of the loop body,
continue语句
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continue statement
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</div> can be used as shortcut.
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[编辑] 关键字

while

[编辑] 为例

#include <iostream>
 
int main()
{
    int i = 0;
    while (i < 10) i++;
 
    std::cout << i << '\n';
 
    int j = 2;
    while (j < 9) {
        std::cout << j << " ";
        j += 2;
    }
}

Output: 

10
2 4 6 8
来自“http://zh.cppreference.com/mwiki/index.php?title=cpp/language/while&oldid=28523”