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

distance = 0
for i in range(len(X)):
    for j in range(len(X)):
        ij_distance = abs(X[i] - X[j])
        if ij_distance == 0:
            continue
        if distance == 0 or ij_distance < distance:
            distance = ij_distance

print(str(distance))