N = int(input())
X = list(map(int,input().split()))
X.sort()
    
ans=10**8
for i in range(N-1):
    if abs(X[i+1]-X[i])!=0:
        ans=min(ans,abs(X[i+1]-X[i]))

if ans==10**8:
    print(0)
else:
    print(ans)