Compilare: main.cpp: In function 'int main()': main.cpp:15:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cerere.in","r",stdin); ^ main.cpp: In function 'void next()': main.cpp:53:49: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] if (r++==limit) fread(sir,1,limit,stdin),r=0; ^