ZOJ Problem Set - 3068
In a certain course, you take n tests. If you get ai out of bi questions correct on test i, your cumulative average is defined to be
Given your test scores and a positive integer k, determine how high you can make your cumulative average if you are allowed to drop any k of your test scores.
Suppose you take 3 tests with scores of 5/5, 0/1, and 2/6. Without dropping any tests, your cumulative average is 100 * (5+0+2) / (5+1+6) = 50. However, if you drop the third test, your cumulative average becomes 100 * (5+0) / (5+1) ~= 83.33 ~= 83.
The input test file will contain multiple test cases, each containing exactly three lines. The first line contains two integers, 1 <= n <= 1000 and 0 < k < n. The second line contains n integers indicating ai for all i. The third line contains n positive integers indicating bi for all i. It is guaranteed that 0 <= ai <= bi <= 1, 000, 000, 000. The end-of-file is marked by a test case with n = k = 0 and should not be processed. For example:
3 1 5 0 2 5 1 6 4 2 1 2 7 9 5 6 7 9 0 0
For each test case, write a single line with the highest cumulative average possible after dropping k of the given test scores. The average should be rounded to the nearest integer. For example:
To avoid ambiguities due to rounding errors, the judge tests have been constructed so that all answers are at least 0.001 away from a decision boundary (i.e., you can assume that the average is never 83.4997).
Source: 2005 Stanford Local Programming Contest