Compilare: main.cpp: In function 'int main()': main.cpp:16:7: warning: statement has no effect [-Wunused-value] for(c;c<b;++c){ ^ main.cpp:11:12: warning: unused variable 'a' [-Wunused-variable] long long a,b,c; ^ main.cpp:9:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.in","r",stdin); ^ main.cpp:10:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("armonica.out","w",stdout); ^ main.cpp:14:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%lld",&b); ^