package main

import (
	"bufio"
	"fmt"
	"os"
	"sort"
	"strconv"
	"strings"
)

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Scan()
	N, _ := strconv.Atoi(sc.Text())
	xs := make([]int, N)
	sc.Scan()
	strs := strings.Split(sc.Text(), " ")
	for i := range strs {
		xs[i], _ = strconv.Atoi(strs[i])
	}
	sort.Ints(xs)
	min := 1000001
	for i := 0; i < N-1; i++ {
		if xs[i+1]-xs[i] < min && xs[i+1] != xs[i] {
			min = xs[i+1] - xs[i]
		}
	}
	if min == 1000001 {
		fmt.Println("0")
	} else {
		fmt.Println(min)
	}
}