N = int(input())
X = sorted(list(map(int, input().split())))

ans = []
for i in range(N-1):
    if abs(X[i] - X[i+1]) == 0:
        pass
    else:
        ans.append(abs(X[i] - X[i+1]))
        
if ans == []:
    print(0)
else:
    print(min(ans))