Compilare: user.cpp: In function ‘char read_ch()’: user.cpp:20:33: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(in_buff,1,4096,fin); ^ user.cpp: In function ‘void ssnd(long long int)’: user.cpp:86:5: warning: ‘n’ may be used uninitialized in this function [-Wmaybe-uninitialized] for(int i=0;i<=n;i++) ^