import sys

def solve():
    input = sys.stdin.read
    data = input().split()
    if not data:
        return
    
    n = int(data[0])
    h = [int(x) for x in data[1:]]
    
    dp = [0] * n
    dp[0] = 0
    dp[1] = abs(h[1] - h[0])
    
    for i in range(2, n):
        dp[i] = min(dp[i - 1] + abs(h[i] - h[i - 1]), dp[i - 2] + abs(h[i] - h[i - 2]))
    
    print(dp[n - 1])

solve()