def msort(x):
    result = []
    if len(x) < 20:
        return sorted(x)
    mid = int(len(x) / 2)
    y = msort(x[:mid])
    z = msort(x[mid:])
    i = 0
    j = 0
    while i < len(y) and j < len(z):
        if y[i] > z[j]:
            result.append(z[j])
            j += 1
        else:
            result.append(y[i])
            i += 1
    result += y[i:]
    result += z[j:]
    return result

def abs(n):
    if n<0:
        return -n
    else:
        return n

#main
N = long(raw_input().strip())
L1 = map(long, raw_input().strip().split(' '))
L = msort(L1)

mind = abs(L[1]-L[0]);
for i in range (2, N):
    mind = min(mind, abs(L[i]-L[i-1]))

print mind