1466. 【2022.7.8】棍子 sticks

https://sjzezoj.com/submission/53557

S2OJ/1466/1466.cpp

@@ -0,0 +1,50 @@
+#include <iostream>
+#include <algorithm>
+#include <functional>
+#include <iomanip>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 55;
+const double eps = 1e-10;
+
+int n, c, k, a[N];
+
+bool check(double x) {
+    int t = std::lower_bound(a + 1, a + 1 + n, static_cast<int>(x), std::greater<int>()) - a;
+
+    if (n + c - (n - t + 1) < k) return false;  // 最坏情况时无法满足要求
+
+    int cnt = 0;
+    for (int i = 1; i <= t; i++) {
+        cnt += a[i] / x;  // 能拆成几个满足要求的
+    }
+
+    return cnt >= k;
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> c >> k;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i];
+    }
+
+    std::sort(a + 1, a + 1 + n, std::greater<int>());
+
+    double l = 0, r = 1e9;
+    for (int i = 0; i < 1000; i++) {
+        double mid = (l + r) / 2;
+
+        (check(mid) ? l : r) = mid;
+    }
+
+    cout << std::fixed << std::setprecision(12) << l << endl;
+
+    return 0;
+}