Compilare: user.cpp: In function ‘int main()’: user.cpp:41:19: warning: unused variable ‘a’ [-Wunused-variable] long long s=0,a,b,x,rez=0,z; ^ user.cpp:41:21: warning: unused variable ‘b’ [-Wunused-variable] long long s=0,a,b,x,rez=0,z; ^ user.cpp:41:25: warning: unused variable ‘rez’ [-Wunused-variable] long long s=0,a,b,x,rez=0,z; ^~~ user.cpp:41:31: warning: unused variable ‘z’ [-Wunused-variable] long long s=0,a,b,x,rez=0,z; ^ user.cpp:42:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("k1.in","r",stdin); ^ user.cpp:43:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("k1.out","w",stdout); ^ user.cpp: In function ‘char getChar()’: user.cpp:18:28: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(BUF,LIM,1,stdin); ^