Median of Two Sorted Arrays

Both lists are sorted in ascending order. Find the median of all their numbers together; for an even count it is the average of the two middle values. An O(log(m + n)) partition search is possible, but any correct method within the limits is accepted.

Implement median_of_two(first, second).

Input

first: A sorted list. second: A sorted list.

Output

Return the median.

制約

0 ≤ lengths ≤ 100,000; the combined length is at least 1

例

入力：
first = [1, 3]
second = [2]

期待される出力：
expected = 2.0

入力：
std::vector<long long> first = {1, 3};
std::vector<long long> second = {2};

期待される出力：
double expected = 2.0;

入力：
long[] first = new long[] {1, 3};
long[] second = new long[] {2};

期待される出力：
double expected = 2.0;

入力：
first = [1, 2]
second = [3, 4]

期待される出力：
expected = 2.5

入力：
std::vector<long long> first = {1, 2};
std::vector<long long> second = {3, 4};

期待される出力：
double expected = 2.5;

入力：
long[] first = new long[] {1, 2};
long[] second = new long[] {3, 4};

期待される出力：
double expected = 2.5;

参考資料

この課題はCodeUtility用に調整されています。上記の説明と制約に従ってください。

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