Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
# 貰うDPだと0へのアクセスが、配るDPだとn+1へのアクセスが必要になる
h = [INF] + list(map(int, input().split())) + [INF]
dp = [INF] + [INF] * n + [INF]
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

# 貰うDP(dp[i-1], dp[i-2]が計算済み)
#for i in range(2, n+1):
#    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
#    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

# 配るDB(dp[i]が計算済み)
#for i in range(1, (n-1)+1):
#    chmin(dp, i+1, dp[i] + abs(h[i] - h[i+1]))
#    chmin(dp, i+2, dp[i] + abs(h[i] - h[i+2]))
#
#print(dp[n])

# 再帰(DFS) (メモ化なし)
def dfs(i):
    if i == 0:
        return INF
    if i == 1:
        return 0

    ans = INF
    prev_cost = dfs(i-1)
    if ans > prev_cost + abs(h[i] - h[i-1]):
        ans = prev_cost + abs(h[i] - h[i-1])
    prev_cost = dfs(i-2)
    if ans > prev_cost + abs(h[i] - h[i-2]):
        ans = prev_cost + abs(h[i] - h[i-2])

    return ans

# 再帰(DFS) (メモ化ありfunctools.lru_cache使用)
import functools
dfs = functools.lru_cache(maxsize=None)(dfs)

print(dfs(n))  


Fixed submission:
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
h = [0] + list(map(int, input().split()))
dp = [INF] + [INF] * n
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

for i in range(2, n+1):
    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

print(dp[n])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
# 貰うDPだと0へのアクセスが、配るDPだとn+1へのアクセスが必要になる
h = [INF] + list(map(int, input().split())) + [INF]
dp = [INF] + [INF] * n + [INF]
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

# 貰うDP(dp[i-1], dp[i-2]が計算済み)
#for i in range(2, n+1):
#    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
#    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

# 配るDB(dp[i]が計算済み)
#for i in range(1, (n-1)+1):
#    chmin(dp, i+1, dp[i] + abs(h[i] - h[i+1]))
#    chmin(dp, i+2, dp[i] + abs(h[i] - h[i+2]))
#
#print(dp[n])

# 再帰(DFS) (メモ化なし)
def dfs(i):
    if i == 0:
        return INF
    if i == 1:
        return 0

    ans = INF
    prev_cost = dfs(i-1)
    if ans > prev_cost + abs(h[i] - h[i-1]):
        ans = prev_cost + abs(h[i] - h[i-1])
    prev_cost = dfs(i-2)
    if ans > prev_cost + abs(h[i] - h[i-2]):
        ans = prev_cost + abs(h[i] - h[i-2])

    return ans

# 再帰(DFS) (メモ化ありfunctools.lru_cache使用)
import functools
dfs = functools.lru_cache()(dfs)

print(dfs(n))  

Fixed submission:
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
h = [0] + list(map(int, input().split()))
dp = [INF] + [INF] * n
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

for i in range(2, n+1):
    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

print(dp[n])

Buggy python submission (verdict: Time Limit Exceeded):
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
# 貰うDPだと0へのアクセスが、配るDPだとn+1へのアクセスが必要になる
h = [INF] + list(map(int, input().split())) + [INF]
dp = [INF] + [INF] * n + [INF]
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

# 貰うDP(dp[i-1], dp[i-2]が計算済み)
#for i in range(2, n+1):
#    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
#    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

# 配るDB(dp[i]が計算済み)
#for i in range(1, (n-1)+1):
#    chmin(dp, i+1, dp[i] + abs(h[i] - h[i+1]))
#    chmin(dp, i+2, dp[i] + abs(h[i] - h[i+2]))
#
#print(dp[n])

# 再帰(DFS) (メモ化なし)
def dfs(i):
    if i == 0:
        return INF
    if i == 1:
        return 0

    ans = INF
    prev_cost = dfs(i-1)
    if ans > prev_cost + abs(h[i] - h[i-1]):
        ans = prev_cost + abs(h[i] - h[i-1])
    prev_cost = dfs(i-2)
    if ans > prev_cost + abs(h[i] - h[i-2]):
        ans = prev_cost + abs(h[i] - h[i-2])

    return ans

print(dfs(n))


Fixed submission:
import sys
input = sys.stdin.readline
sys.setrecursionlimit(10 ** 7)

INF = 10 ** 10

n = int(input())
h = [0] + list(map(int, input().split()))
dp = [INF] + [INF] * n
dp[1] = 0

def chmin(dp_table, index, value):
    if dp_table[index] > value:
        dp_table[index] = value

for i in range(2, n+1):
    chmin(dp, i, dp[i-1] + abs(h[i] - h[i-1]))
    chmin(dp, i, dp[i-2] + abs(h[i] - h[i-2]))

print(dp[n])