func (c *LRU) RemoveOldest() (key string, value uint64, ok bool) {
	ent := c.evictList.Back()
	if ent != nil {
		c.removeElement(ent)
		kv := ent.Value.(*entry)
		return kv.key, kv.value, true
	}
	return "", 0, false
}
func (c *LRU) RemoveOldest() (key string, value uint64, ok bool) {
	ent := c.evictList.Back()
	if ent != nil {
		c.removeElement(ent)
		kv := ent.Value.(*entry)
		return kv.key, kv.value, true
	}
	return "", 0, false
}
func ( c * LRU ) RemoveOldest ( ) ( key string , value uint64 , ok bool ) { ent := c . evictList . Back ( ) if ent != nil { c . removeElement ( ent ) kv := ent . Value . ( * entry ) return kv . key , kv . value , true } return " " , 0 , false }
// RemoveOldest removes the oldest item from the cache.
RemoveOldest removes the oldest item from the cache .