n = int(input())

numList = list(map(int, input().split()))
ret = None
for i in range(n):
    if (i == n - 1):
        break

    val = abs(numList[i] - numList[i + 1])
    if i == 0:
        ret = val
        continue
    elif (val == 0):
        continue
    elif (ret > val):
        ret = val

if ret == None:
    ret = 0

print(ret)