package main

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

func main() {
	sc := NewScanner(os.Stdin)
	N, _ := sc.NextInt()
	X := make([]int, N)
	for i := 0; i < N; i++ {
		X[i], _ = sc.NextInt()
	}
	sort.Ints(X)
	min := 0
	for i := 1; i < N; i++ {
		d := X[i] - X[i-1]
		switch {
		case d == 0:
			continue
		case min == 0:
			min = d
		case min > d:
			min = d
		}
	}
	fmt.Println(min)
}

type Scanner struct {
	*bufio.Scanner
}

func NewScanner(r io.Reader) *Scanner {
	return &Scanner{
		bufio.NewScanner(r),
	}
}

func (s *Scanner) Next() (string, error) {
	s.Scanner.Split(bufio.ScanWords)
	return s.nextToken()
}

func (s *Scanner) nextToken() (string, error) {
	sc := s.Scanner
	if sc.Scan() {
		return sc.Text(), nil
	}
	if sc.Err() != nil {
		return "", sc.Err()
	}
	return "", io.EOF
}

func (s *Scanner) NextInt() (int, error) {
	token, err := s.Next()
	if err != nil {
		return 0, err
	}
	return strconv.Atoi(token)
}