package main

import (
	"fmt"
	"sort"
)

func min(x, y int) int {
	if y < x {
		return y
	}
	return x
}

const inf = 1 << 30

func main() {
	var n int
	fmt.Scan(&n)
	m := make(map[int]bool)
	for i := 0; i < n; i++ {
		var x int
		fmt.Scan(&x)
		m[x] = true
	}
	a := make([]int, 0, n)
	for k := range m {
		a = append(a, k)
	}
	sort.Ints(a)
	if len(a) < 2 {
		fmt.Println(0)
		return
	}
	res := inf
	for i := 1; i < len(a); i++ {
		res = min(res, a[i]-a[i-1])
	}
	fmt.Println(res)
}