Submission #5118510

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Source Code Expand

N, D = map(int, input().split())

A, B, C = 0, 0, 0
while D%2==0:
    A += 1
    D //= 2
while D%3==0:
    B += 1
    D //= 3
while D%5==0:
    C += 1
    D //= 5

if D > 1:
    print(0)
else:
    X = [[[0] * (C+1) for _ in range(B+1)] for __ in range(A+1)]
    X[0][0][0] = 1
    for i in range(N):
        Y = [[[0] * (C+1) for _ in range(B+1)] for __ in range(A+1)]
        for a in range(A+1):
            for b in range(B+1):
                for c in range(C+1):
                    Y[min(a+1, A)][min(b+1, B)][c] += X[a][b][c]/6 # 6
                    Y[min(a+1, A)][b][c] += X[a][b][c]/6 # 2
                    Y[min(a+2, A)][b][c] += X[a][b][c]/6 # 4
                    Y[a][min(b+1, B)][c] += X[a][b][c]/6 # 3
                    Y[a][b][min(c+1, C)] += X[a][b][c]/6 # 5
                    Y[a][b][c] += X[a][b][c]/6 # 1
        X = Y
    print("{:.10f}".format(X[-1][-1][-1]))
    

Submission Info

Judge Result