#P10908. [蓝桥杯 2024 国 B] 选数概率
[蓝桥杯 2024 国 B] 选数概率
Problem Description
In an array, there are copies of , copies of , and copies of . Let denote the probability that when two numbers are chosen at random from the array, one number is and the other number is . For example, , where is a binomial coefficient, meaning the number of ways to choose elements from distinct elements.
When , it holds that $P_{1,2}=\dfrac{517}{2091},P_{2,3}=\dfrac{2632}{10455},P_{1,3}=\dfrac{308}{2091}$, and is minimal. It is guaranteed that the solution with minimal is unique.
You need to submit a string in the format . For example, if your computed result is , then the string you need to submit is 12,34,56.
Input Format
This is an output-only fill-in-the-blank problem. You only need to compute the result and submit it. The result of this problem is an integer. When submitting the answer, only fill in this integer; any extra content will result in no score.
Output Format
This is an output-only fill-in-the-blank problem. You only need to compute the result and submit it. The result of this problem is an integer. When submitting the answer, only fill in this integer; any extra content will result in no score.
Hint
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