Compilare: user.cpp: In function ‘void eliminare(char)’: user.cpp:36:34: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(!op.empty()&&p[op.top()]>=p[s]) ^ user.cpp:36:40: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(!op.empty()&&p[op.top()]>=p[s]) ^ user.cpp: In function ‘void semn(int&)’: user.cpp:47:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<in.size()&&isalpha(in[i])) ^ user.cpp:45:9: warning: unused variable ‘j’ [-Wunused-variable] int j; ^ user.cpp: In function ‘int main()’: user.cpp:76:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<in.size();i++) ^ user.cpp:79:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(i<in.size()&&isalpha(in[i])) ^ user.cpp:71:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j; ^