C++实现平方的安全方法（redis的实现）
?
/* Our hash table capability is a power of two */static unsigned long _dictNextPower(unsigned long size){ unsigned long i = DICT_HT_INITIAL_SIZE; //DICT_HT_INITIAL_SIZE=4 if (size >= LONG_MAX) return LONG_MAX; while(1) { if (i >= size) return i; i *= 2; }}