Problem G. Math Magic
时间限制 2000 ms
内存限制 32 MB
Yesterday, my teacher taught us about math: +, -, *, /, GCD, LCM... As you know, LCM (Least common multiple) of two positive numbers can be solved easily because of a * b = GCD (a, b) * LCM (a, b).
In class, I raised a new idea: “how to calculate the LCM of K numbers”. It's also an easy problem indeed, which only cost me 1 minute to solve it. I raised my hand and told teacher about my outstanding algorithm. Teacher just smiled and smiled...
After class, my teacher gave me a new problem and he wanted me solve it in 1 minute, too.
If we know three parameters N, M, K, and two equations:
1. SUM (A
1, A
2, ..., A
i, A
i+1,..., A
K) = N
2. LCM (A
1, A
2, ..., A
i, A
i+1,..., A
K) = M
Can you calculate how many kinds of solutions are there for A
i (A
i are all positive numbers).
I began to roll cold sweat but teacher just smiled and smiled.
Can you solve this problem in 1 minute?
输入数据
输出数据
For each test case, output an integer indicating the number of solution modulo 1,000,000,007(10
9 + 7).
You can get more details in the sample and hint below.
样例输入
样例输出
样例说明
The first test case: the only solution is (2, 2). The second test case: the solution are (1, 2) and (2, 1).
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