#1805. 【2017.3长乐省选集训Day2T3】阅读

https://sjzezoj.com/submission/66027

S2OJ/1805/1805.cpp

@@ -0,0 +1,84 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 1e5 + 5;
+const long long INF = 0x3f3f3f3f'3f3f3f3f;
+
+struct node {
+    long long max;
+    node *lchild, *rchild;
+
+    node()
+        : max(-INF), lchild(nullptr), rchild(nullptr) {}
+
+    void pushup() {
+        max = -INF;
+
+        if (lchild) max = std::max(max, lchild->max);
+        if (rchild) max = std::max(max, rchild->max);
+    }
+};
+
+int k, m, d, a, n, t[N], b[N];
+long long f[N];
+node *root;
+
+void modify(node *&cur, int l, int r, int x, long long v) {
+    if (!cur) cur = new node();
+
+    if (l == r) {
+        cur->max = v;
+
+        return;
+    }
+
+    int mid = l + r >> 1;
+
+    if (x <= mid) modify(cur->lchild, l, mid, x, v);
+    else modify(cur->rchild, mid + 1, r, x, v);
+
+    cur->pushup();
+}
+
+long long query(node *cur, int l, int r, int ql, int qr) {
+    if (!cur) return -INF;
+    if (ql <= l && r <= qr) return cur->max;
+
+    int mid = l + r >> 1;
+    long long res = -INF;
+
+    if (ql <= mid) res = std::max(res, query(cur->lchild, l, mid, ql, qr));
+    if (qr > mid) res = std::max(res, query(cur->rchild, mid + 1, r, ql, qr));
+
+    return res;
+}
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> k >> m >> d >> a >> n;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> t[i] >> b[i];
+    }
+
+    t[0] = k, t[n + 1] = m;
+
+    modify(root, 0, d - 1, t[0] % d, static_cast<long long>(t[0]) / d * a);
+
+    for (int i = 1; i <= n + 1; i++) {
+        f[i] = std::max(
+                   query(root, 0, d - 1, 0, (t[i] - 1) % d),
+                   query(root, 0, d - 1, (t[i] - 1) % d + 1, d - 1) + a)
+             - static_cast<long long>(t[i] - 1) / d * a - a + b[i];
+        modify(root, 0, d - 1, t[i] % d, f[i] + static_cast<long long>(t[i]) / d * a);
+    }
+
+    cout << f[n + 1] << endl;
+
+    return 0;
+}