在 do while 循环中的 continue 语句

Question

#include <stdlib.h>
#include <stdio.h> 
enum {false, true}; 
    
int main() 
{ 
   int i = 1; 
   do
   { 
      printf("%d\n", i); 
      i++; 
      if (i < 15) 
        continue; 
   } while (false); 
      
   getchar(); 
   return 0; 
} 

continue 之后会发生什么在这段代码中执行语句？
控制去哪儿了？

Answer 1

下一条语句将是 while (false);结束 do-while循环后执行 getchar();一般来说:

do
{
    ...
    statements
    ...

    continue;   // Act as "GOTO continue_label"

    ...
    statements
    ...

continue_label:
} while (...);

如果您想尝试一下，可以使用以下代码:

int i = 0;
do
{
    printf("After do\n");
    ++i;
    if (i < 2) 
    {
        printf("Before continue\n");
        continue;
    }
    printf("Before while\n");
} while(printf("Inside while\n") && i < 2);

输出+注释来解释:

After do              // Start first loop
Before continue       // Execute continue, consequently "Before while" is not printed
Inside while          // Execute while
After do              // Start second loop
Before while          // Just before the while (i.e. continue not called in this loop)
Inside while          // Execute while