/in/foo.c: In function 'main':
/in/foo.c:31:13: warning: 'd' may be used uninitialized [-Wmaybe-uninitialized]
   31 |         int a3=n/d;
      |             ^~
/in/foo.c:19:15: note: 'd' was declared here
   19 |         int c,d,max;//d为最大公约数
      |               ^