package main

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

func nextInt(sc *bufio.Scanner) int {
	sc.Scan()
	t, _ := strconv.Atoi(sc.Text())
	return t
}

func main() {
	sc := bufio.NewScanner(os.Stdin)
	sc.Split(bufio.ScanWords)
	N := nextInt(sc)
	X := make(map[int]int, 0)
	for i := 0; i < N; i++ {
		X[nextInt(sc)]++
	}
	ks := make([]int, 0)
	for k := range X {
		ks = append(ks, k)
	}
	sort.Ints(ks)
	// fmt.Println("N", N, "X", X, "ks", ks)
	var ans int
	if len(ks) > 1 {
		ans = int(1e7) + 1
		for i := 1; i < len(ks); i++ {
			ans = min(ans, ks[i]-ks[i-1])
		}
	}
	fmt.Println(ans)
}
func min(a, b int) int {
	if a < b {
		return a
	}
	return b
}