题目描述：
LeetCode 571. Find Median Given Frequency of Numbers
The Numbers table keeps the value of number and its frequency.
+----------+-------------+ | Number | Frequency | +----------+-------------| | 0 | 7 | | 1 | 1 | | 2 | 3 | | 3 | 1 | +----------+-------------+
In this table, the numbers are 0, 0, 0, 0 ...