How to Solve Minimum Difference Problem

Given two arrays, sorted and exactly the same length, write a function that finds a pair of numbers, one from each of the arrays,such that the difference between both is as small as possible.

Input:
[0, 3, 5, 8, 10], [6, 9, 12, 13, 14]
Output:
[5, 6]

Input:
[7.12, 15, 20, 21], [1, 5, 9, 13, 17]
Output:
[12, 13]

Input:
[6, 10, 15, 18, 21], [16, 17, 18, 23, 27]
Output:
[8, 8]

package main

import (
    "fmt"
)

func diff(n int) int {
    if n < 0 {
        return n * -1
    }
    return n
}

func minDiff(a []int, b []int) (int, int) {
    min := -1
    var result1, result2 int
    for i, j := 0, 0; i < len(a) && j < len(b); {
        newMin := diff(a[i] - b[j])
        if min == -1 {
            min = newMin
            result1, result2 = a[i], b[j]
        } else {
            if newMin < min {
                min = newMin
                result1, result2 = a[i], b[j]
            }
        }
        if a[i] < b[j] {
            i++
        } else {
            j++
        }
    }
    return result1, result2
}

func main() {
    fmt.Println(minDiff([]int{0, 3, 5, 8, 10}, []int{6, 9, 12, 13, 14}))
    fmt.Println(minDiff([]int{7, 12, 15, 20, 21}, []int{1, 5, 9, 13, 17}))
    fmt.Println(minDiff([]int{6, 10, 15, 18, 21}, []int{16, 17, 18, 23, 27}))
}