Compilare: user.cpp: In function ‘int main()’: user.cpp:67:37: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1,buff_size, stdin); ^ user.cpp: In function ‘void read(int&)’: user.cpp:15:111: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] while(buff[pos] < '0' || buff[pos] > '9') if(++pos == buff_size) fread(buff, 1,buff_size, stdin), pos = 0; ^ user.cpp:20:73: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(++pos == buff_size) fread(buff, 1, buff_size, stdin), pos = 0; ^ user.cpp: In function ‘int main()’: user.cpp:78:42: warning: ‘maxij’ may be used uninitialized in this function [-Wmaybe-uninitialized] write(maxii);putChar(' ');write(maxij);putChar('\n'); ^ user.cpp:78:16: warning: ‘maxii’ may be used uninitialized in this function [-Wmaybe-uninitialized] write(maxii);putChar(' ');write(maxij);putChar('\n'); ^