twosortedarray.go

func findMedianSortedArrays(nums1 []int, nums2 []int) float64 {
	p1l, p1r := 0, len(nums1)
	p2l, p2r := 0, len(nums2)

	m := float64(p1r+p2r-1) / 2

	for i := int(m); i > 0; i-- {
		if p1l == p1r {
			p2l++
		} else if p2l == p2r {
			p1l++
		} else if nums1[p1l] < nums2[p2l] {
			p1l++
		} else {
			p2l++
		}
	}

	var sum, t float64

	if m == float64(int(m)) {
		t = 1 // m
	} else {
		t = 2 // m, m+1
	}

	for i := int(t); i > 0; i-- {
		if p1l == p1r {
			sum += float64(nums2[p2l])
			p2l++
		} else if p2l == p2r {
			sum += float64(nums1[p1l])
			p1l++
		} else if nums1[p1l] < nums2[p2l] {
			sum += float64(nums1[p1l])
			p1l++
		} else {
			sum += float64(nums2[p2l])
			p2l++
		}
	}

	return sum / t
}