oj.uz

Submission #66498

# Submission time Handle Problem Language Result Execution time Memory
66498 2018-08-11T03:13:52 Z kingpig9 Collapse (JOI18_collapse) C++11
30 / 100
 3027 ms 25296 KB 
#include <bits/stdc++.h>
#include "collapse.h"

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const int MAXN = 1e5 + 160;
const int SQRT = 320;

//#define debug(...) fprintf(stderr, __VA_ARGS__)
#define debug(...)
#define fi first
#define se second
#define all(v) (v).begin(), (v).end()
#define fillchar(a, s) memset((a), (s), sizeof(a))

int N, C, Q;
int T[MAXN], X[MAXN], Y[MAXN];	//Edges
int E[MAXN];	//edge ID.
int W[MAXN], P[MAXN];	//Queries
int ans[MAXN];

struct union_find {
	int par[MAXN];
	stack<pair<int*, int>> chng;	//god fucking damn it. used vector not stack. Then used a "forall" loop on it. But you need to go backward NOT forward iterating through this container!!!
	bool active;
	int ncomp;

	void reset() {
		for (int i = 0; i < N; i++) {
			par[i] = i;
		}
		ncomp = N;
		assert(chng.empty());
		active = false;
	}

	void change (int &x, int y) {
		if (active) {
			chng.push(make_pair(&x, x));
		}
		x = y;
	}

	int find (int x) {
		if (x == par[x]) {
			return x;
		}
		change(par[x], find(par[x]));
		return par[x];
	}

	void merge (int x, int y) {
		x = find(x);
		y = find(y);
		if (x == y) {
			return;
		}
		change(par[x], y);
		change(ncomp, ncomp - 1);
	}

	void rollback() {
		while (!chng.empty()) {
			*(chng.top().fi) = chng.top().se;
			chng.pop();
		}
	}
};

int death[MAXN];	//death time of edge.
vector<pii> queries[MAXN];	//queries[day] = vector(position, id)
union_find uf;
int estl[MAXN], estr[MAXN], tmp[MAXN];

bool cmpr (int a, int b) {
	return Y[a] < Y[b];
}

bool cmpl (int a, int b) {
	return X[a] > X[b];
}

void solve() {
	//X, Y = roads constructed
	//w, P = questions.
	/*
	//they aren't vectors but global arrays.
	assert(X.size() == C);
	assert(Y.size() == C);
	assert(W.size() == Q);
	assert(P.size() == Q);
	*/

	for (int i = 0; i < Q; i++) {
		queries[W[i]].push_back({P[i], i});
	}

	for (int sday = 0; sday < C; sday += SQRT) {
		int eday = min(sday + SQRT, C);
		//what is the stuff before sday? certainly need to add this in.
		vector<array<int, 3>> vqu;
		for (int i = sday; i < eday; i++) {
			for (pii p : queries[i]) {
				vqu.push_back({p.fi, i, p.se});
			}
		}

		//ok let's now go to this now.

		int posr = 0;	//position of estr
		//prefix
		debug("-------start prefix----------\n");
		
		sort(all(vqu));
		uf.reset();

		//preliminary add edge if: it is born before sday (edgeid < sday) and if it dies >= eday (death[edgeid] >= eday)
		for (auto q : vqu) {
			int pos = q[0];
			for (; posr < sday && Y[estr[posr]] <= q[0]; posr++) {
				int edgeid = estr[posr];
				debug("death[%d] = %d\n", edgeid, eday);
				//assert(death[edgeid] >= eday);
				if (edgeid < sday && death[edgeid] >= eday) {
					uf.merge(X[edgeid], Y[edgeid]);
					debug("merge %d %d\n", X[edgeid], Y[edgeid]);
				}
			}

			//need this
			for (int i = sday; i < eday; i++) {
				uf.find(X[i]);
				uf.find(Y[i]);
			}

			uf.active = true;
			debug("--active--\n");
			//then merge the rest of them!
			for (int i = sday; i <= q[1]; i++) {
				//is this a valid merge?
				debug("Start with ncomp = %d\n", uf.ncomp);
				if (Y[i] <= pos) {
					debug("find(1) == find(56)? %d. find(60) == find(72)? %d.\n", (uf.find(1) == uf.find(56)), (uf.find(60) == uf.find(72)));	//this is for the specific test data in "cbad.in" - it gets 36 not 35 in original buggy code for the first query (35 is correct answer)

					//only add edge if: born <= q[1] (edgeid <= q[1]) -- this is actually 100% going to happen here -- and not dead yet (death[edgeid] > q[1])
					int edgeid = E[i];
					assert(edgeid <= q[1]);
					if (death[edgeid] > q[1]) {
						uf.merge(X[i], Y[i]);
						debug("merge %d %d\n", X[i], Y[i]);
					}
				}
			}

			ans[q[2]] += uf.ncomp;
			debug("answer[%d] += %d\n", q[2], uf.ncomp);
			uf.rollback();
			uf.active = false;
			debug("--inactive--\n");
		}

		debug("-------start suffix----------\n");
		//suffix

		uf.reset();
		reverse(all(vqu));

		int posl = 0;
		for (auto q : vqu) {
			int pos = q[0];
			//note: strictly greater than q[0]
			for (; posl < sday && X[estl[posl]] > q[0]; posl++) {
				int edgeid = estl[posl];
				if (edgeid < sday && death[edgeid] >= eday) {
					uf.merge(X[edgeid], Y[edgeid]);
					debug("merge %d %d\n", X[edgeid], Y[edgeid]);
				}

			}
			//need this
			for (int i = sday; i < eday; i++) {
				uf.find(X[i]);
				uf.find(Y[i]);
			}

			debug("--active--\n");
			uf.active = true;
			for (int i = sday; i <= q[1]; i++) {
				if (X[i] > pos) {
					int edgeid = E[i];
					if (death[edgeid] > q[1]) {
						uf.merge(X[i], Y[i]);
						debug("merge %d %d\n", X[i], Y[i]);
					}
				}
			}

			ans[q[2]] += uf.ncomp - N;
			debug("answer[%d] += %d; answer[%d] -= N\n", q[2], uf.ncomp, q[2]);
			uf.rollback();
			debug("--inactive--\n");
			uf.active = false;
		}


		//then add the new edges
		vector<int> nedge;
		for (int i = sday; i < eday; i++) {
			nedge.push_back(i);
		}
		sort(all(nedge), cmpl);
		copy(tmp, merge(estl, estl + sday, all(nedge), tmp, cmpl), estl);
		sort(all(nedge), cmpr);
		copy(tmp, merge(estr, estr + sday, all(nedge), tmp, cmpr), estr);
	}
}

vector<int> simulateCollapse (int n, vector<int> ttt, vector<int> xxx, vector<int> yyy, vector<int> www, vector<int> ppp) {
	//globalize the variables
	N = n;
	C = xxx.size();
	Q = www.size();
	for (int i = 0; i < C; i++) {
		T[i] = ttt[i];
		X[i] = xxx[i];
		Y[i] = yyy[i];
	}
	for (int i = 0; i < Q; i++) {
		W[i] = www[i];
		P[i] = ppp[i];
	}

	map<pii, vector<int>> mpind;
	for (int i = 0; i < C; i++) {
		if (X[i] > Y[i]) {
			swap(X[i], Y[i]);
		}
		pii p(X[i], Y[i]);
		if (T[i] == 1) {
			//remove it
			int ind = mpind.at(p).back();
			death[ind] = i;
			E[i] = ind;
			mpind.at(p).pop_back();
		} else {
			death[i] = C;
			E[i] = i;
			mpind[p].push_back(i);
		}
	}

	solve();
	return vector<int> (ans, ans + Q);
}

Subtask #1
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 3320 KB Output is correct
2 Correct 7 ms 3320 KB Output is correct
3 Correct 8 ms 3320 KB Output is correct
4 Correct 11 ms 3320 KB Output is correct
5 Incorrect 18 ms 3472 KB Output isn't correct
6 Halted 0 ms 0 KB -

Subtask #2
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 90 ms 8420 KB Output is correct
2 Correct 60 ms 8420 KB Output is correct
3 Incorrect 409 ms 14644 KB Output isn't correct
4 Halted 0 ms 0 KB -

Subtask #3
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 50 ms 14644 KB Output is correct
2 Correct 64 ms 14644 KB Output is correct
3 Correct 80 ms 14644 KB Output is correct
4 Correct 127 ms 14644 KB Output is correct
5 Correct 522 ms 14644 KB Output is correct
6 Correct 538 ms 14644 KB Output is correct
7 Correct 1341 ms 20508 KB Output is correct
8 Correct 2443 ms 24860 KB Output is correct
9 Correct 59 ms 24860 KB Output is correct
10 Correct 571 ms 24860 KB Output is correct
11 Correct 2709 ms 25244 KB Output is correct
12 Correct 2827 ms 25244 KB Output is correct
13 Correct 3027 ms 25292 KB Output is correct
14 Correct 2906 ms 25292 KB Output is correct
15 Correct 2871 ms 25296 KB Output is correct

Subtask #4
0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 3320 KB Output is correct
2 Correct 7 ms 3320 KB Output is correct
3 Correct 8 ms 3320 KB Output is correct
4 Correct 11 ms 3320 KB Output is correct
5 Incorrect 18 ms 3472 KB Output isn't correct
6 Halted 0 ms 0 KB -