foo.cc: In function '__int128 AlGO::FastIO::Read()':
foo.cc:33:29: warning: 'last' may be used uninitialized [-Wmaybe-uninitialized]
   33 |             return last=='-'?-s:s;
      |                    ~~~~~~~~~^~~~~
foo.cc:30:39: note: 'last' was declared here
   30 |             int s=0;char ch=getchar(),last;
      |                                       ^~~~

Found 10 testcases.
[Hydro](https://hydro.ac)提供评测服务