Median-of-Two-Sorted-Arrays

Catalog

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Calculate the medians m1 and m2 of the input arrays ar1[] and ar2[] respectively. 個別計算input陣列 ar1, ar2 的中間值 m1, m2。
If m1 and m2 both are equal then we are done. 當 m1=m2 則完成計算。
```
return m1 (or m2)
```
If m1 is greater than m2, then median is present in one of the below two subarrays. 當假若m1>m2 則切分出以下2種 (ar1, ar2) 的新陣列。

a. From first element of ar1 to m1 (ar1[0...|n/2|])

b. From m2 to last element of ar2 (ar2[|n/2|...n-1])
If m2 is greater than m1, then median is present in one of the below two subarrays. 當m2>m1 則反之亦然。

a. From m1 to last element of ar1 (ar1[|n/2|...n-1])

b. From first element of ar2 to m2 (ar2[0...|n/2|])
Repeat the above process until size of both the subarrays becomes 2. 重複上述步驟直到 2. m1, m2相等時回傳。
If size of the two arrays is 2 then use below formula to get the median. 此外，當兩input陣列長度為2時最快的方式，就直接找兩陣列下的最大值及最小值即可。
```
Median = (max(ar1[0], ar2[0]) + min(ar1[1], ar2[1]))/2
```