比如说 java Object[] objcts 这种保存对象的数组和基本类型的类型的数组会不同吗？
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比如说 java Object[] objcts 这种保存对象的数组和基本类型的类型的数组会不同吗？
一样快，数组在初始化的时候就分配了数组大小的连续内存地址。所以根据索引下标直接取对应下标的值。对于 Object[]，它里面实际存放的是对象的引用。Object[]和普通类型的数组的区别只是前者存放的是Object，自然可以是所有继承自Object的对象都可以，如int，shot, String等，后者只能存放声明的基本类型
对于你刚才给出的例子来说，是一样快
是一样快的，都是根据索引来判断地址取值的。
一样快的,PHP数组用hashTable实现,每个键值对(其实是键名)会被hash一次,放入制定的bucket,数字索引不需要hash,如果有冲突就用链接法接在之前一个元素后面,hashTable里面包含两个指针:
Bucket pListHead; / 数组头元素指针 */
Bucket pListTail; / 数组尾元素指针 */
所以是无论取第一个还是第二个都是一样的.
对了,顺便说一下,hashTable是一个结构体,里面还有一个一个成员:
uint nNumOfElements;
用count()函数返回就是整个值,所以count其实并没有遍历数组
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