Compilare: main.cpp: In function 'char adv()': main.cpp:4:86: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] const int S=(1<<17);char buf[S];int ptr=S;char adv(){if (ptr==S){fread(buf,1,S,stdin);ptr=0;}return buf[ptr++];} ^ main.cpp: In function 'int main()': main.cpp:8:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("permutariab.in","r",stdin);freopen ("permutariab.out","w",stdout); ^ main.cpp:8:76: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen ("permutariab.in","r",stdin);freopen ("permutariab.out","w",stdout); ^