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
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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 . However, if you drop the third test, your cumulative average becomes .
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 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.
3 1 5 0 2 5 1 6 4 2 1 2 7 9 5 6 7 9 0 0Sample Output
83 100Hint
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).
#include<cstdio> #include<cstring> #include<string> #include<algorithm> #include<cmath> using namespace std; const int maxn = 2005; const int INF = 0x3f3f3f3f; int n, m; double a[maxn]; double b[maxn]; double t[maxn]; double judge(double k) { double ans = 0; for (int i = 0; i < n; i++) { t[i] = a[i] - b[i] * k; } sort(t, t + n); for (int i = m; i < n; i++) ans += t[i]; return ans; } int main() { while (scanf_s("%d%d", &n, &m) != EOF ) { if (n + m == 0) break; for (int i = 0; i < n; i++) scanf_s("%lf", &a[i]); for (int i = 0; i < n; i++) scanf_s("%lf", &b[i]); double l = 0.0; double r = 1.0; while (r-l >1e-7) { double mid = (l + r) / 2; if (judge(mid) > 0) l = mid; else r = mid; } printf("%1.f\n", l * 100); } return 0; }