Buggy python submission (verdict: Runtime Error):
N = int(input())
Alist = list(map(float, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max([ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj)])
    memo[cur_N][ai] = ret
    return ret
print(int(ddp(0, Alist[0])))

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Buggy python submission (verdict: Runtime Error):
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max([ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj)])
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Buggy python submission (verdict: Runtime Error):
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max((ai + ddp(cur_N+1, aj)), (-1*ai + ddp(cur_N+1, -1*aj)))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Buggy python submission (verdict: Runtime Error):
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    nx = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, nx), -1*ai + ddp(cur_N+1, -1*nx))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Buggy python submission (verdict: Runtime Error):
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    nx = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, nx), -ai + ddp(cur_N+1, -nx))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))

Fixed submission:
import sys
sys.setrecursionlimit(10**6)
N = int(input())
Alist = list(map(int, input().split()))
memo = [{} for i in range(N)]

def ddp(cur_N, ai):
    if ai in memo[cur_N]:
        return memo[cur_N][ai]
    if cur_N >=N-1:
        return ai
    aj = Alist[cur_N+1]
    ret = max(ai + ddp(cur_N+1, aj), -1*ai + ddp(cur_N+1, -1*aj))
    memo[cur_N][ai] = ret
    return ret
print(ddp(0, Alist[0]))