Leetcode Note: Go - Find Nearest Point That Has the Same X or Y Coordinate

func nearestValidPoint(x int, y int, points [][]int) int {
    var res int = -1
    
    smallestDistance := 1 << 63 - 1
    
    for i := 0; i < len(points); i++ {
        if points[i][0] == x || points[i][1] == y {
            if distance([]int{x, y}, points[i]) < smallestDistance {
                smallestDistance = distance([]int{x, y}, points[i])
                res = i
            }
        }
    }
    
    return res
}

func distance(a []int, b[]int) int {
    return (a[0] - b[0])*(a[0] - b[0]) + (a[1] - b[1])*(a[1] - b[1])
}