n = int(input())
x = list(map(int,input().split()))
x.sort()
ans = 1000000
a = 0
for i in range(n-1):
    y = (x[i+1])-(x[i])
    if y == 0:
        continue
    elif y<=ans:
        ans = y
        a +=1
if a == 0:
    print(0)
else:
    print(ans)