백준 12996 acka

풀이는 나중에 작성...

memo = dict()
song = list(map(int, input().split()))
n = song[0]

def solve(n, song):
    if n==0:
        if song[0] == song[1] == song[2] == 0: return 1
        else: return 0
    
    if (song[0], song[1], song[2], n) in memo:
        return memo[(song[0], song[1], song[2], n)]

    res = 0
    for i in range(1, 8):
        a=song[0] - (i&1>0)
        b=song[1] - (i&2>0)
        c=song[2] - (i&4>0)
        if a<0 or b<0 or c<0: continue
        res+=solve(n-1, [a, b, c])
    memo[(song[0], song[1], song[2], n)] = res%1_000_000_007
    # print(res, n)
    return memo[(song[0], song[1], song[2], n)]

print(solve(n, song[1:]))

https://www.acmicpc.net/source/52542954
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