/in/foo.cc:2:11: error: '::main' must return 'int'
 void main()
           ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:8:3: error: 'c' was not declared in this scope
   c=getchar();//用c来存单词间的空格
   ^
/in/foo.cc:9:9: error: 'c' was not declared in this scope
  }while(c!='\n');//此循环用于存储句子
         ^