foo.cc: In function 'void solve()':
foo.cc:43:16: error: found ':' in nested-name-specifier, expected '::'
   43 |         for(it : divisor[a[i]]) nextGc[it] = sz - 5;
      |                ^
      |                ::
foo.cc:43:13: error: 'it' has not been declared
   43 |         for(it : divisor[a[i]]) nextGc[it] = sz - 5;
      |             ^~
foo.cc:44:5: error: expected primary-expression before '}' token
   44 |     }
      |     ^
foo.cc:43:53: error: expected ';' before '}' token
   43 |         for(it : divisor[a[i]]) nextGc[it] = sz - 5;
      |                                                     ^
      |                                                     ;
   44 |     }
      |     ~                                                
foo.cc:44:5: error: expected primary-expression before '}' token
   44 |     }
      |     ^
foo.cc:43:53: error: expected ')' before '}' token
   43 |         for(it : divisor[a[i]]) nextGc[it] = sz - 5;
      |            ~                                        ^
      |                                                     )
   44 |     }
      |     ~                                                
foo.cc:44:5: error: expected primary-expression before '}' token
   44 |     }
      |     ^