foo.cc: In function ‘int main()’:
foo.cc:31:27: warning: ‘x’ may be used uninitialized [-Wmaybe-uninitialized]
   31 |                 ans = ans * x % P;
      |                       ~~~~^~~
foo.cc:25:21: note: ‘x’ was declared here
   25 |                 int x;
      |                     ^