/in/foo.cc: In function 'int main()':
/in/foo.cc:8:16: error: 'strlen' was not declared in this scope
  int m=strlen(A);
                ^
/in/foo.cc:14:10: error: invalid types 'char[int]' for array subscript
    if(A[i]==B[j])
          ^
/in/foo.cc:14:16: error: invalid types 'char[int]' for array subscript
    if(A[i]==B[j])
                ^
/in/foo.cc:16:8: error: invalid types 'char[int]' for array subscript
     A[i]=' ';
        ^