class Problem0135:
	def solve(this):
		n = int(input())
		x = sorted(list(map(int,input().split())))
		
		res = []
		for i in range(len(x) - 1):
			d = abs(x[i+1] - x[i])
			if d != 0:
				res.append(d)
		print(min(res))
		
if __name__ == "__main__":
	problem = Problem0135()
	problem.solve()