Compilare: user.cpp: In function ‘int main()’: user.cpp:52:13: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(!dq[st].empty()) { ^ user.cpp:54:13: warning: array subscript has type ‘char’ [-Wchar-subscripts] val=dq[st].front().val+1; ^ user.cpp:60:15: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(!dq[dr].empty() && val>=dq[dr].back().val) dq[dr].pop_back(); ^ user.cpp:60:38: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(!dq[dr].empty() && val>=dq[dr].back().val) dq[dr].pop_back(); ^ user.cpp:60:57: warning: array subscript has type ‘char’ [-Wchar-subscripts] while(!dq[dr].empty() && val>=dq[dr].back().val) dq[dr].pop_back(); ^ user.cpp:61:8: warning: array subscript has type ‘char’ [-Wchar-subscripts] dq[dr].push_back({val,i}); ^ user.cpp:42:11: warning: unused variable ‘c’ [-Wunused-variable] int n,c,x,i,k,res=0,j,val; ^ user.cpp:42:13: warning: unused variable ‘x’ [-Wunused-variable] int n,c,x,i,k,res=0,j,val; ^