n = int(input())
x = list(map(int,input().split()))

delta_list = []
sorted_x = sorted(x)
for i in range(n - 1):
    delta = sorted_x[i+1] - sorted_x[i]
    if delta > 0:
        delta_list.append(sorted_x[i+1] - sorted_x[i])
    
if len(delta_list) == 0:
    print(res)
else:
    print(min(delta_list))