a = raw_input()
b = raw_input()
c = b.split()
d = []
for i in range(0,len(c)):
    d.append(int(c[i]))
m = abs(d[0] - d[1])
n = 0
for i in range(0, len(d)):
    for j in range(i+1, len(d)):
        n = abs(d[i]-d[j])
        if n < m:
            m = n
print m