/in/foo.cc: In function 'int solve(ll)':
/in/foo.cc:24:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if(ret<0) ret+=mod;if(ret>=mod) ret-=mod;
  ^~
/in/foo.cc:24:21: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
  if(ret<0) ret+=mod;if(ret>=mod) ret-=mod;
                     ^~
/in/foo.cc: In function 'int main()':
/in/foo.cc:28:11: warning: unused variable 'T' [-Wunused-variable]
  ll n;int T;
           ^