Compilare: user.cpp:19:21: warning: multi-character character constant [-Wmultichar] cout << '0 \n' ; ^ user.cpp: In function ‘int main()’: user.cpp:10:11: warning: unused variable ‘a’ [-Wunused-variable] int n,a,ma=0,ck=0,p1=0,p2=0; ^ user.cpp:10:18: warning: unused variable ‘ck’ [-Wunused-variable] int n,a,ma=0,ck=0,p1=0,p2=0; ^ user.cpp:10:28: warning: unused variable ‘p2’ [-Wunused-variable] int n,a,ma=0,ck=0,p1=0,p2=0; ^