Compilare: user.cpp: In function ‘void comb(int, int, int, FILE*)’: user.cpp:11:15: warning: unused variable ‘ok’ [-Wunused-variable] int i,ok = 0; ^ user.cpp: In function ‘int main()’: user.cpp:28:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&k); ^