Compilare: user.cpp: In function ‘int main()’: user.cpp:24:15: warning: array subscript has type ‘char’ [-Wchar-subscripts] Q[s[i]].push(i); ^ user.cpp:42:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] Q[s[i]].pop(); ^ user.cpp:17:10: warning: unused variable ‘ch’ [-Wunused-variable] char ch; ^ user.cpp:41:9: warning: ‘poz’ may be used uninitialized in this function [-Wmaybe-uninitialized] while (i <= poz) { ^