/in/foo.cc: In function 'bool check()':
/in/foo.cc:12:17: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for(int j=0;j<L[i].size();j++)
                ~^~~~~~~~~~~~
/in/foo.cc:14:26: warning: array subscript has type 'char' [-Wchar-subscripts]
           lw=lw+w[L[i][j]];
                          ^
/in/foo.cc:15:20: warning: array subscript has type 'char' [-Wchar-subscripts]
     rw=rw+w[R[i][j]];
                    ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:36:38: warning: array subscript has type 'char' [-Wchar-subscripts]
        for(char k='A';k<='L';k++) w[k]=1;
                                      ^
/in/foo.cc:40:16: warning: array subscript has type 'char' [-Wchar-subscripts]
             w[k]=0;
                ^
/in/foo.cc:47:11: warning: array subscript has type 'char' [-Wchar-subscripts]
        w[k]=2;
           ^
/in/foo.cc:54:8: warning: array subscript has type 'char' [-Wchar-subscripts]
     w[k]=1;  
        ^