/in/foo.cc: In function 'int FindSecondMax(int*, int)':
/in/foo.cc:21:22: warning: 'max2' may be used uninitialized [-Wmaybe-uninitialized]
   21 |         while (a[x2] != max2) x2++;//x2即为第二大值的下标
      |                ~~~~~~^~~~~~~
/in/foo.cc:10:13: note: 'max2' was declared here
   10 |         int max2;
      |             ^~~~