#3633. Pair

http://www.nfls.com.cn:20035/submission/592121

NFLSOJ/0/3633/3633.cpp

@@ -0,0 +1,90 @@
+// #include <iostream>
+#include <algorithm>
+#include <cstring>
+#include <fstream>
+#include <utility>
+
+// using std::cin;
+// using std::cout;
+std::ifstream cin("pair.in");
+std::ofstream cout("pair.out");
+const char endl = '\n';
+
+const int N = 2e5 + 5,
+          M = (1 << 8) + 5;
+
+int n, q, max_pre[M][N], max_suf[M][N], max_val[M][M][(1 << 9) + 5][2];
+std::pair<int, int> a[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    cin >> n;
+
+    for (int i = 1; i <= n; i++) {
+        cin >> a[i].first >> a[i].second;
+    }
+
+    std::sort(a + 1, a + 1 + n, [&](const auto &lhs, const auto &rhs) -> bool { return (lhs.first & 0x1ff) < (rhs.first & 0x1ff); });
+
+    for (int i = 0; i < 1 << 8; i++) {
+        max_pre[i][0] = max_suf[i][n + 1] = 0;
+
+        for (int j = 1; j <= n; j++) {
+            max_pre[i][j] = std::max(max_pre[i][j - 1], (i + (a[j].first >> 9)) ^ (a[j].second >> 9));
+        }
+
+        for (int j = n; j; j--) {
+            max_suf[i][j] = std::max(max_suf[i][j + 1], (i + (a[j].first >> 9)) ^ (a[j].second >> 9));
+        }
+    }
+
+    memset(max_val, 0xff, sizeof(max_val));
+
+    for (int i = 1; i <= n; i++) {
+        for (int j = 0; j <= 0x1ff; j++) {
+            max_val[a[i].first >> 9][a[i].second >> 9][j][j + (a[i].first & 0x1ff) >= 0x200] = std::max(
+                max_val[a[i].first >> 9][a[i].second >> 9][j][j + (a[i].first & 0x1ff) >= 0x200],
+                ((j + a[i].first) ^ a[i].second) & 0x1ff);
+        }
+    }
+
+    cin >> q;
+
+    while (q--) {
+        int t, l = 1, r = n, res = 1;
+
+        cin >> t;
+
+        while (l <= r) {
+            int mid = l + r >> 1;
+
+            if ((t & 0x1ff) + (a[mid].first & 0x1ff) < 0x200) {
+                l = mid + 1;
+                res = mid;
+            } else {
+                r = mid - 1;
+            }
+        }
+
+        int high = std::max(max_pre[t >> 9][res], max_suf[(t >> 9) + 1][res + 1]),
+            low = -1;
+
+        for (int i = 0; i <= 0xff; i++) {
+            int j = (high ^ i) - (t >> 9);
+
+            if (0 <= j && j <= 0xff) {
+                low = std::max(low, max_val[j][i][t & 0x1ff][0]);
+            }
+
+            if (0 <= j - 1 && j - 1 <= 0xff) {
+                low = std::max(low, max_val[j - 1][i][t & 0x1ff][1]);
+            }
+        }
+
+        cout << (high << 9 | low) << endl;
+    }
+
+    return 0;
+}