n = int(input()) a = list(map(int,input().split())) # dis = 10**8 # for i in range(n): # for j in range(n): # if i!=j: # d = abs( a[i] - a[j]) # if d< dis: # dis =d # print(dis) a.sort() dis = a[1]-a[0] for i in range(1,n-2): # print( a[i+1]-a[i]) if a[i+1]-a[i]< dis: dis = a[i+1]-a[i] print(dis)