4004. [JLOI2015]装备购买

https://hydro.ac/d/bzoj/record/6322f021bdf9bc31d160a3f3

BZOJ/4004/4004.cpp

@@ -0,0 +1,76 @@
+#include <iostream>
+#include <algorithm>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 505;
+const double eps = 1e-4;
+
+int n, m, ans, sum;
+double p[N][N];
+
+struct node {
+    int w;
+    double v[N];
+
+    double& operator[](const int& _i) {
+        return v[_i];
+    }
+
+    bool operator<(const node& _y) const {
+        return w < _y.w;
+    }
+} q[N];
+
+inline bool insert(double* a) {
+    for (int i = 1; i <= m; i++) {
+        if (std::abs(a[i]) > eps) {
+            if (std::abs(p[i][i]) > eps) {  // > 0
+                double k = a[i] / p[i][i];
+                for (int j = i; j <= m; j++) {
+                    a[j] -= k * p[i][j];
+                }
+            } else {
+                for (int j = i; j <= m; j++) {
+                    p[i][j] = a[j];
+                }
+
+                return true;
+            }
+        }
+    }
+
+    return false;
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n >> m;
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 1; j <= m; j++) {
+            cin >> q[i][j];
+        }
+    }
+
+    for (int i = 1; i <= n; i++) {
+        cin >> q[i].w;
+    }
+
+    std::sort(q + 1, q + 1 + n);
+
+    for (int i = 1; i <= n; i++) {
+        if (insert(q[i].v)) {
+            ans++;
+            sum += q[i].w;
+        }
+    }
+
+    cout << ans << ' ' << sum << endl;
+
+    return 0;
+}