41 lines
1.1 KiB
C++
41 lines
1.1 KiB
C++
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#include <cstdio>
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#include <iostream>
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#include <algorithm>
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#include <cmath>
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using namespace std;
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const int N = 1010;
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const int INF = 0x3f3f3f3f;
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int n, k;
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int a[N], b[N];
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const double eps = 1e-8;
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double d[N];
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bool check(double x) {
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for (int i = 0; i < n; i++) d[i] = a[i] - x * b[i];
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sort(d, d + n, greater<double>()); //由大到小排序
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double sum = 0;
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for (int i = 0; i < n - k; i++) sum += d[i];
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return sum >= 0; //从大到小选n-k个，看ans是否为可行的解
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}
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int main() {
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while (cin >> n >> k && (n || k)) {
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for (int i = 0; i < n; i++) cin >> a[i];
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for (int i = 0; i < n; i++) cin >> b[i];
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//浮点数二分
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double l = 0, r = INF;
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while (r - l > eps) {
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double mid = (l + r) / 2; //注意浮点数不能用右移操作
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if (check(mid))
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l = mid; //向右逼近，使结果更大一些
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else
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r = mid; //向左逼近，使结果更小一些
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}
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printf("%.0lf\n", l * 100); // 四舍五入
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}
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return 0;
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}
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