[LeetCode]Search Insert Position (二分查找总结) Java Version

原题：https://oj.leetcode.com/submissions/detail/10707421/

需要注意的是，不能用beg = mid来更新，因为当beg和end相邻的时候，mid == beg。

public class Solution {
public int searchInsert(int[] A, int target) {
int beg = 0, end = A.length - 1, mid, res;

if(target == A[end]) return end;
if(target > A[end]) return end + 1;
if(target <= A[beg]) return beg;

while(beg < end)
{
mid = beg + (end - beg) / 2;

if(A[mid] < target)
beg = mid + 1;
else if(A[mid] == target)
return mid;
else
end = mid; //when end pass through end, the loop will stop.
}

res = beg;

return res;
}
}