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61 lines
982 B
C++
61 lines
982 B
C++
#include <iostream>
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#include <algorithm>
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#include <iomanip>
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using std::cin;
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using std::cout;
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const char endl = '\n';
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const int N = 1e5 + 5;
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const double eps = 1e-7;
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int n, k, a[N], b[N];
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double c[N];
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inline bool check(double mid) {
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double sum = 0;
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for (int i = 1; i <= n; i++) {
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c[i] = static_cast<double>(a[i]) - mid * b[i];
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}
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std::sort(c + 1, c + 1 + n, std::greater<>());
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for (int i = 1; i <= k; i++) {
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sum += c[i];
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}
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return sum >= 0;
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}
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int main() {
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std::ios::sync_with_stdio(false);
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cin.tie(nullptr);
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cin >> n >> k;
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for (int i = 1; i <= n; i++) {
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cin >> a[i];
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}
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for (int i = 1; i <= n; i++) {
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cin >> b[i];
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}
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double l = 0, r = 1e9;
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while (r - l > eps) {
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double mid = (l + r) / 2;
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if (check(mid)) {
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l = mid;
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} else {
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r = mid;
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}
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}
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cout << std::fixed << std::setprecision(4) << l << endl;
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return 0;
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}
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