Question

我有一个程序可以读取用户的输入并将其打印在单独的行上。我正在尝试创建一个循环并退出循环，并在输入“退出”时终止程序。

例如，如果用户输入句子“退出该程序，程序将读取该句子并仅打印quit然后退出程序（不在单独的行上打印其余的句子）

这是我的代码：

  <select class="styleclass" id="fencelist">
    <option selected disabled hidden>Choose here</option>
    <option value="Arrow">Arrow</option>
  </select>

  <select class="styleclass" id="stylelist">
    <option selected disabled hidden>Choose here</option>
    <option value="Fence">Fence</option>
    <option value="1 Door Gate">1 Door Gate</option>
    <option value="2 Door Gate">2 Door Gate</option>
  </select>`

  <select class="styleclass" id="panellist">
    <option selected disabled hidden>Choose here</option>
    <option value="Spear">Spear</option>
    <option value="Triad">Triad</option>
  </select>

  <select class="styleclass" id="raillist">
    <option selected disabled hidden>Choose here</option>
    <option value="Scroll">Scroll</option>
    <option value="Circle">Circle</option>
    <option value="X">X</option>
  </select>

Answer 1

要在流中查找序列，每当一个字符与当前索引的字符匹配时，就将索引增加到触发序列。如果不匹配，请重置计数器。如果索引到达触发序列的末尾，则操作完成：

int quit_index = 0 ;
const char* quit_trigger = "quit" ;

// read up to 100 characters from stdin, print each word on a line
// until the quit trigger sequence is read.
while( quit_trigger[quit_index] != 0
       n < MAXC && 
       (c = getchar ()) != EOF && c != '\n')
{
    if (c == ' ')
        printf ("\n");
    else
        printf ("%c", c);
    n++;

    // While sequence matches the trigger sequence, increment index, 
    // otherwise reset to zero on mismatch.
    quit_index = (c == quit_trigger[quit_index]) ? quit_index + 1 : 0 ;
}

退出循环并终止C程序中的程序

1 个答案: