Compilare: user.cpp: In function ‘char divide_et_impera(long long int, long long int, long long int, int)’: user.cpp:11:17: warning: unused variable ‘hz’ [-Wunused-variable] int hz = 0,ak = 0;; ^ user.cpp:11:24: warning: unused variable ‘ak’ [-Wunused-variable] int hz = 0,ak = 0;; ^ user.cpp:24:17: warning: unused variable ‘hz’ [-Wunused-variable] int hz = 0,ak = 0;; ^ user.cpp:24:24: warning: unused variable ‘ak’ [-Wunused-variable] int hz = 0,ak = 0;; ^ user.cpp: In function ‘int main()’: user.cpp:66:12: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] in >> s+1; ^ user.cpp: In function ‘char divide_et_impera(long long int, long long int, long long int, int)’: user.cpp:62:1: warning: control reaches end of non-void function [-Wreturn-type] } ^