Compilare: user.cpp: In function ‘void Solve(int, int)’: user.cpp:30:45: warning: array subscript has type ‘char’ [-Wchar-subscripts] while ( !St.empty() && Ap[S[St.top()]-'a'] > 1 && S[i] <= S[St.top()] ){ ^ user.cpp:30:77: warning: array subscript has type ‘char’ [-Wchar-subscripts] while ( !St.empty() && Ap[S[St.top()]-'a'] > 1 && S[i] <= S[St.top()] ){ ^ user.cpp:31:26: warning: array subscript has type ‘char’ [-Wchar-subscripts] Ap[S[St.top()]-'a']--; ^ user.cpp:32:23: warning: array subscript has type ‘char’ [-Wchar-subscripts] S[St.top()] = 'X'; ^ user.cpp:40:26: warning: array subscript has type ‘char’ [-Wchar-subscripts] marked[S[St.top()]-'a'] = 1; ^ user.cpp: In function ‘int main()’: user.cpp:50:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf ( f, "%d%*c%s", &N, S+1 ); ^