Create nocross.cpp

Changes

1 changed files (+57/-0)

• 2017/February/Platinum/nocross.cpp (new)
  • @@ -0,0 +1,57 @@
    + #include <algorithm> + #include <iostream> + #include <fstream> + #include <string> + #include <vector> + #include <queue> + #include <set> + #include <map> + #include <unordered_set> + #include <unordered_map> + #include <cmath> + #include <cstring> + using namespace std; + typedef long long ll; + typedef pair<int, int> ii; + typedef vector<int> vi; + typedef vector<ii> vii; + constexpr auto INF = (int)1e9; + constexpr auto MAXN = 100005; + + int N, A[100005], B[100005], R[100005], seg[4 * MAXN] = { 0 }; + + void update(int x, int v, int l = 0, int r = -1, int n = 1) { + if (r == -1) r = N - 1; + if (l == r) seg[n] = max(v, seg[n]); + else { + int m = (l + r) >> 1; + x <= m ? update(x, v, l, m, n << 1) : update(x, v, m + 1, r, n << 1 | 1); + seg[n] = max(seg[n << 1], seg[n << 1 | 1]); + } + } + + int query(int a, int b, int l = 0, int r = -1, int n = 1) { + if (r == -1) r = N - 1; + if (l > b || r < a) return 0; + if (l >= a && r <= b) return seg[n]; + int m = (l + r) >> 1; + return max(query(a, b, l, m, n << 1), query(a, b, m + 1, r, n << 1 | 1)); + } + + int main() { + ifstream cin("nocross.in"); + ofstream cout("nocross.out"); + + cin >> N; + for (int i = 0; i < N; ++i) cin >> A[i], A[i]--; + for (int i = 0; i < N; ++i) cin >> B[i], B[i]--; + for (int i = 0; i < N; ++i) R[B[i]] = i; + + for (int i = 0; i < N; ++i) { + vii u; + for (int j = max(A[i] - 4, 0); j < min(A[i] + 5, N); ++j) u.emplace_back(R[j], query(0, R[j] - 1) + 1); + for (auto q : u) update(q.first, q.second); + } + + cout << query(0, N - 1) << endl; + }