折半查找的算法。将数列按有序化(递增或递减)排列，查找过程中采用跳跃式方式查找，即先以有序数列的中点位置为比较对象，如果要找的元素值小于该中点元素，则将待查序列缩小为左半部分，否则为右半部分。通过一次比较，将查找区间缩小一半。 -Binary search algorithm. The series by ordering (ascending or descending) order, find the process of using leap way to find that the first series of the mid-point of an orderly place to compare objects to find the element if the value is less than the midpoint of the element, will reduce the left part of the sequence of unknown origin, otherwise the right half. Through a comparison, will narrow the search interval by half.