commonPrefix.go

commonPrefix.go

package main

import "fmt"

func commonPrefix(values ...string) string {
    vLen := len(values)
    if vLen < 1 {
        return ""
    }
    minIndex := 0
    min := values[0]
    minLen := len(min)

    for i := 1; i < vLen; i += 1 {
        st := values[i]
        if st == "" {
            return ""
        }
        lst := len(st)
        if lst < minLen {
            min = st
            minLen = lst
            minIndex = i + 0
        }
    }

    prefix := make([]byte, minLen)
    matchOn := true
    for i := 0; i < minLen; i += 1 {
        for j, other := range values {
            if minIndex == j {
                continue
            }
            if other[i] != min[i] {
                matchOn = false
                break
            }
        }
        if !matchOn {
            break
        }
        prefix[i] = min[i]
    }
    return string(prefix)
}

func main() {
    prefix := commonPrefix("/mnt/openSrc", "/mnt//", "/mnt/custom", "/mnt/openSrc/io.js")
    fmt.Println(prefix) // Should return "/mnt/"
    prefix = commonPrefix("/usr/lib/openSrc", "/mnt//", "/mnt/openSrc/io.js")
    fmt.Println(prefix) // Should return "/"
}