def main():
    n = int(input())
    l = sorted(list(map(int, input().split())))

    ans = 10 ** 10
    for i in range(len(l) - 1):
        if l[i] == l[i + 1]:
            continue
        ans = min(ans, abs(l[i] - l[i + 1]))

    print(ans if ans != 10 ** 10 else 0)
    
if __name__ == '__main__':
    main()