import math

n = int(input())
points = list(set([int(i) for i in input().split()]));
points.sort();

dist = 1000010;
if len(points) == 1:
    dist = 0
else:
    for i in range(len(points) - 1):
        dist = min(dist, abs(points[i] - points[i + 1]))
    
print(dist)