/in/foo.cc: In function 'int main()':
/in/foo.cc:24:36: warning: array subscript has type 'char' [-Wchar-subscripts]
   for(int i=0;i<len;++i) ++num[s[i]];
                                    ^
/in/foo.cc:25:38: warning: array subscript has type 'char' [-Wchar-subscripts]
   for(char i='A';i<='Z';++i) if(num[i]) q.push(num[i]),tot++,cout<<num[i]<<" ";cout<<endl;
                                      ^
/in/foo.cc:25:53: warning: array subscript has type 'char' [-Wchar-subscripts]
   for(char i='A';i<='Z';++i) if(num[i]) q.push(num[i]),tot++,cout<<num[i]<<" ";cout<<endl;
                                                     ^
/in/foo.cc:25:73: warning: array subscript has type 'char' [-Wchar-subscripts]
   for(char i='A';i<='Z';++i) if(num[i]) q.push(num[i]),tot++,cout<<num[i]<<" ";cout<<endl;
                                                                         ^
/in/foo.cc:25:3: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
   for(char i='A';i<='Z';++i) if(num[i]) q.push(num[i]),tot++,cout<<num[i]<<" ";cout<<endl;
   ^~~
/in/foo.cc:25:80: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
   for(char i='A';i<='Z';++i) if(num[i]) q.push(num[i]),tot++,cout<<num[i]<<" ";cout<<endl;
                                                                                ^~~~
/in/foo.cc:27:13: warning: unused variable 'f3' [-Wunused-variable]
   int f1,f2,f3;
             ^~