Card game

"""
def solve(left, right, x, r):

    if (left, right) in r:
        return r[(left, right)]
    
    if right - left < 3:
        return 0
    elif right - left == 3:
        return x[left+1]
    else:
        output = 0
        
        for i in range(left, right-2):
            a, b = left, i
            val = x[i+1]
            c, d = i+3, right
            output = max(output, solve(a, b, x, r) + val + solve(c, d, x, r))

        r[(left, right)] = output
        return output

def solve2(left, right, x, r):

    if (left, right) in r:
        return r[(left, right)]
    
    if right - left < 3:
        return 0
    elif right - left == 3:
        return x[left+1]
    elif right - left == 4:
        return max(x[left+1], x[left+2])
    else:
        output = max(
            x[left+1] + solve2(left+3, right, x, r),
            x[left+2] + solve2(left+4, right, x, r),
            x[left+3] + solve2(left+5, right, x, r)
        )
        r[(left, right)] = output
        return output
"""

def iterative(x):

    n = len(x)
    r = [0] * (n+1)
    r[3] = x[-2]
    r[4] = max(x[-3], x[-2])

    for i in range(5, n+1):
        r[i] = max(x[n-i+1] + r[i-3], x[n-i+2] + r[i-4], x[n-i+3] + r[i-5])

    return r[n]

int(input(""))
print(iterative([int(e) for e in input("").split(" ")]))

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 57, in <module>
    p...

Test 12

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 57, in <module>
    p...

Test 13

Verdict: RUNTIME ERROR

Traceback (most recent call last):
  File "/box/input/code.py", line 57, in <module>
    p...

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED