#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 aa copies of 11, bb copies of 22, and cc copies of 33. Let Pi,jP_{i,j} denote the probability that when two numbers are chosen at random from the array, one number is ii and the other number is jj. For example, P1,2=abC(a+b+c,2)P_{1,2} = \dfrac{ab}{C(a+b+c,2)}, where C(N,M)C(N, M) is a binomial coefficient, meaning the number of ways to choose MM elements from NN distinct elements.

When a=?,b=?,c=?a=\text{?},b=\text{?},c=\text{?}, it holds that $P_{1,2}=\dfrac{517}{2091},P_{2,3}=\dfrac{2632}{10455},P_{1,3}=\dfrac{308}{2091}$, and a+b+ca + b + c is minimal. It is guaranteed that the solution with minimal a+b+ca + b + c is unique.

You need to submit a string in the format a,b,ca,b,c. For example, if your computed result is a=12,b=34,c=56a = 12, b = 34, c = 56, 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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