package main

import (
	"fmt"
	"math"
	"sort"
)

func abs(a int) int {
	return int(math.Abs(float64(a)))
}

func min(a, b int) int {
	return int(math.Min(float64(a), float64(b)))
}

func resolve(N int, X []int) int {
	ret := 1000001
	sort.Ints(X)
	for i := 0; i < N-1; i++ {
		if X[i] == X[i+1] {
			continue
		}
		ret = min(ret, abs(X[i]-X[i+1]))
	}
	if ret == 1000001 {
		return 0
	}
	return ret
}

func main() {
	var N int

	fmt.Scanf("%d\n", &N)

	X := make([]int, N)
	for i := 0; i < N; i++ {
		fmt.Scanf("%d", &X[i])
	}

	fmt.Println(resolve(N, X))
}