标签：
Numbers keep coming, return the median of numbers at every time a new number added.
Have you met this question in a real interview?For numbers coming list: [1, 2, 3, 4, 5], return [1, 1, 2, 2, 3].
For numbers coming list: [4, 5, 1, 3, 2, 6, 0], return [4, 4, 4, 3, 3, 3, 3].
For numbers coming list: [2, 20, 100], return [2, 2, 20].
Total run time in O(nlogn).
What‘s the definition of Median?- Median is the number that in the middle of a sorted array. If there are n numbers in a sorted array A, the median isA[(n - 1) / 2]. For example, if
A=[1,2,3], median is 2. If A=[1,19], median is
1.
[思路]
[CODE]
public class Solution {
/**
* @param nums: A list of integers.
* @return: the median of numbers
*/
public int[] medianII(int[] nums) {
// write your code here
if(nums==null) return null;
int[] res = new int[nums.length];
PriorityQueue<Integer> minHeap = new PriorityQueue<Integer>();
PriorityQueue<Integer> maxHeap = new PriorityQueue<Integer>(11, new Comparator<Integer>() {
@Override
public int compare(Integer x, Integer y) {
return y-x;
}
});
res[0] = nums[0];
maxHeap.add(nums[0]);
for(int i=1; i<nums.length; i++) {
int x = maxHeap.peek();
if(nums[i] <= x) {
maxHeap.add(nums[i]);
} else {
minHeap.add(nums[i]);
}
if(maxHeap.size() > minHeap.size()+1 ) {
minHeap.add(maxHeap.poll());
} else if(maxHeap.size() < minHeap.size()) {
maxHeap.add(minHeap.poll());
}
res[i] = maxHeap.peek();
}
return res;
}
}
lintcode 1: Data Stream Median
标签：
原文地址：http://blog.csdn.net/xudli/article/details/46389077
