Compilare: user.cpp: In function ‘void solve(int)’: user.cpp:45:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] t[++nrt]=x+'a'; ^ user.cpp:47:16: warning: array subscript has type ‘char’ [-Wchar-subscripts] t[++nrt]=x-26+'A'; ^ user.cpp: In function ‘int main()’: user.cpp:62:11: warning: unused variable ‘j’ [-Wunused-variable] int i,j,a,b; ^ user.cpp: In function ‘int num(char)’: user.cpp:20:1: warning: control reaches end of non-void function [-Wreturn-type] } ^