foo.cc: In function ‘int main()’:
foo.cc:10:22: warning: ‘solve’ may be used uninitialized [-Wmaybe-uninitialized]
   10 |                 solve+=n;
      |                 ~~~~~^~~
foo.cc:5:30: note: ‘solve’ was declared here
    5 |         long long n,g,gonglv,solve;
      |                              ^~~~~