Submission #331038

#	Time	Username	Problem	Language	Result	Execution time	Memory
331038		caoash	Mostovi (COI14_mostovi)	C++17	0 / 100	275 ms	15084 KiB

mostovi

/*
 * Consider some path from u to v.
 *
 * Define the range of some guy u as [u, first before u that has edge cut].
 *
 * Define the range of v similarly.
 *
 * Then if there exists a bridge between [l1, r1] and [l2, r2], then u can reach v.
 *
 * Try to view it as points.
 * 
 * Problem reduces to: add a point, check if rectangle contains point.
 * Another constraint: points are always monotoncially increasing
 * - binary search for first point with x >= left edge of rect and y >= bottom edge of rect
 * - check if x <= right edge of rect and y <= top edge of rect
 */

#include <bits/stdc++.h> 
using namespace std;

using ll = long long;

using vi = vector<int>;
using vl = vector<ll>;
#define pb push_back
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
#define lb lower_bound
#define ub upper_bound

using pi = pair<int,int>;
#define f first
#define s second
#define mp make_pair

const int MX = 200005;
const int MOD = (int) (1e9 + 7);
const ll INF = (ll) 1e18;

namespace output {
  void pr(int x) {
    cout << x;
  }
  void pr(long x) {
    cout << x;
  }
  void pr(ll x) {
    cout << x;
  }
  void pr(unsigned x) {
    cout << x;
  }
  void pr(unsigned long x) {
    cout << x;
  }
  void pr(unsigned long long x) {
    cout << x;
  }
  void pr(float x) {
    cout << x;
  }
  void pr(double x) {
    cout << x;
  }
  void pr(long double x) {
    cout << x;
  }
  void pr(char x) {
    cout << x;
  }
  void pr(const char * x) {
    cout << x;
  }
  void pr(const string & x) {
    cout << x;
  }
  void pr(bool x) {
    pr(x ? "true" : "false");
  }

  template < class T1, class T2 > void pr(const pair < T1, T2 > & x);
  template < class T > void pr(const T & x);

  template < class T, class...Ts > void pr(const T & t,
    const Ts & ...ts) {
    pr(t);
    pr(ts...);
  }
  template < class T1, class T2 > void pr(const pair < T1, T2 > & x) {
    pr("{", x.f, ", ", x.s, "}");
  }
  template < class T > void pr(const T & x) {
    pr("{"); // const iterator needed for vector<bool>
    bool fst = 1;
    for (const auto & a: x) pr(!fst ? ", " : "", a), fst = 0;
    pr("}");
  }

  void ps() {
    pr("\n");
  } // print w/ spaces
  template < class T, class...Ts > void ps(const T & t,
    const Ts & ...ts) {
    pr(t);
    if (sizeof...(ts)) pr(" ");
    ps(ts...);
  }

  void pc() {
    cout << "]" << endl;
  } // debug w/ commas
  template < class T, class...Ts > void pc(const T & t,
    const Ts & ...ts) {
    pr(t);
    if (sizeof...(ts)) pr(", ");
    pc(ts...);
  }
   //#define dbg(x...) pr("[", #x, "] = ["), pc(x);
}

#ifdef mikey 
using namespace output;
#else
using namespace output;
 //#define dbg(x...)
#endif

#include <ext/pb_ds/tree_policy.hpp>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template <class T> using PeanutButter = tree<T, null_type, less<T>, 
    rb_tree_tag, tree_order_statistics_node_update>; 
#define ook order_of_key
#define fbo find_by_order

PeanutButter<pi> pts;
set<int> bad[2];
set<int> pre[2];

int main(){
#ifdef mikey 
    freopen("a.in", "r", stdin);
#endif
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m; cin >> n >> m;
    bad[0].insert(n), bad[1].insert(n);
    pre[0].insert(1), pre[1].insert(1);
    auto has = [&] (pi xs, pi ys) {
        int ans = -1;
        int lo = 0, hi = sz(pts) - 1;
         //dbg(pts);
        while (lo <= hi) {
            int mid = (lo + hi) / 2;
            pi cur = *pts.fbo(mid);
             //dbg(mid, cur);
            if (cur.f >= xs.f && cur.s >= ys.f) {
                hi = mid - 1;
                ans = mid;
            } else {
                lo = mid + 1;
            }
        }
        if (ans == -1) return false;
        else {
            pi cur = *pts.fbo(ans);
             //dbg(cur);
            if (cur.f <= xs.s && cur.s <= ys.s) {
                return true;
            } 
            return false;
        }
    };
    for (int i = 0; i < m; i++) {
        char qt; cin >> qt;
        if (qt == 'A') {
            int x, y; cin >> x >> y;
            if (x > y) swap(x, y);
            if (y > n) y -= n; 
            pts.insert(mp(x, y));
        } else if (qt == 'B') {
            int x, y; cin >> x >> y;
             //dbg("REM", x, y);
            bool c = (x > n);
            x -= (n * c);
            y -= (n * c);
            bad[c].insert(min(x, y));
            pre[c].insert(max(x, y));
        } else {
            int x, y; cin >> x >> y;
            int c = (x > n), c2 = (y > n);
            x -= (n * c);
            y -= (n * c2);
             //dbg("QUERY", x, y);
            if (c == c2) {
                int go = *(bad[c].lb(min(x, y)));
                if (go >= y) cout << "DA\n";
                else cout << "NE\n";
            } else {
                pi r1 = mp(x, *bad[c].lb(x));
                pi r2 = mp(y, *bad[c2].lb(y));
                if (c) {
                    r1 = mp(*(--pre[c].ub(x)), x);
                    r2 = mp(*(--pre[c2].ub(y)), y);
                }
                 //dbg(r1, r2);
                if (has(r1, r2)) cout << "DA\n";
                else cout << "NE\n";
            }
        }
    }
}

• Subtask 1: 0 / 100