Submission #70047262

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import sys
sys.setrecursionlimit(1 << 25)
data = list(map(int, sys.stdin.read().split()))
it = iter(data)
N = next(it)
M = next(it)
A = [next(it) for _ in range(N)]
mid = N // 2
left_list = []
def dfs_left(i, s, last):
    if i >= mid:
        left_list.append((s % M, last))
        return
    dfs_left(i + 1, s, last)
    dfs_left(i + 2, s + A[i], last or (i == mid - 1))
from collections import defaultdict
right0 = defaultdict(int)
right1 = defaultdict(int)
def dfs_right(i, s, first):
 
 
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import sys
sys.setrecursionlimit(1 << 25)
data = list(map(int, sys.stdin.read().split()))
it = iter(data)
N = next(it)
M = next(it)
A = [next(it) for _ in range(N)]
mid = N // 2

left_list = []
def dfs_left(i, s, last):
    if i >= mid:
        left_list.append((s % M, last))
        return
    dfs_left(i + 1, s, last)
    dfs_left(i + 2, s + A[i], last or (i == mid - 1))

from collections import defaultdict
right0 = defaultdict(int)
right1 = defaultdict(int)
def dfs_right(i, s, first):
    if i >= N:
        if first:
            right1[s % M] += 1
        else:
            right0[s % M] += 1
        return
    dfs_right(i + 1, s, first)
    dfs_right(i + 2, s + A[i], first or (i == mid))

dfs_left(0, 0, False)
dfs_right(mid, 0, False)

res = 0
for s, last in left_list:
    target = (-s) % M
    if last:
        res += right0.get(target, 0)
    else:
        res += right0.get(target, 0) + right1.get(target, 0)
print(res)

Submission Info

Judge Result