/in/foo.cc: In function 'int calc()':
/in/foo.cc:47:36: warning: array subscript has type 'char' [-Wchar-subscripts]
    while (n1 > 0 && bond[ id[s1[n1]] ][ id[c] ] == '>') {
                                    ^
/in/foo.cc:47:45: warning: array subscript has type 'char' [-Wchar-subscripts]
    while (n1 > 0 && bond[ id[s1[n1]] ][ id[c] ] == '>') {
                                             ^
/in/foo.cc: In function 'int compute(int, int, char)':
/in/foo.cc:30:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^