oj.uz

Submission #94799

# Submission time Handle Problem Language Result Execution time Memory
94799 2019-01-24T05:30:51 Z shoemakerjo Cats or Dogs (JOI18_catdog) C++14
100 / 100
 598 ms 22848 KB 
#include "catdog.h"
#include <bits/stdc++.h>

using namespace std;

int n;
const int maxn = 100010;
const int inf = 1000000000;

int subsize[maxn];
int bigch[maxn];
int myspot[maxn];
int mycol[maxn]; //store the current color of this node
vector<int> preorder; //this is the special preorder thing
vector<int> adj[maxn];
int par[maxn];
int chainhead[maxn]; //pretty sure this is all that matters 
					 //don't need tail??
int chainend[maxn];

int ccost[maxn][2]; //cost of being colored 1 or 2
int pardiff[maxn][2];

struct mat {
	int v[2][2];
};

const bool debug = false;

mat seg[maxn*4]; 

void printmat(mat & thing) {
	cout << thing.v[0][0] << ", " << thing.v[0][1] << ", " << thing.v[1][0] << 
		", " << thing.v[1][1] << endl;
}

mat merge(mat& a, mat& b) {
	//no reason to not pass by reference
	mat res;
	res.v[0][0] = res.v[0][1] = res.v[1][0] = res.v[1][1] = inf;
	
	for (int i = 0; i <= 1; i++) {
		for (int j = 0; j <= 1; j++) {
			res.v[i][j] = min(res.v[i][j], 
				a.v[i][0] + b.v[0][j]);
			res.v[i][j] = min(res.v[i][j], 
				a.v[i][0] + 1 + b.v[1][j]);
			res.v[i][j] = min(res.v[i][j], 
				a.v[i][1] + 1 + b.v[0][j]);
			res.v[i][j] = min(res.v[i][j], 
				a.v[i][1] + b.v[1][j]);
		}
	}

	// if (debug) {

	// cout << "	merge of ";
	// printmat(a);
	// cout << " 	and ";
	// printmat(b);
	// cout << "	produces ";
	// printmat(res);

	// }

	return res;
}

void predfs(int u, int p = -1) {
	par[u] = p;
	if (debug) cout << u << " has parent " << p << endl;
	subsize[u] = 1;
	for (int v : adj[u]) {
		if (v == p) continue;
		predfs(v, u);
		subsize[u] += subsize[v];
		if (subsize[v] > subsize[bigch[u]]) {
			bigch[u] = v;
		}
	}
}

void dfs(int u) {
	preorder.push_back(u);
	myspot[u] = preorder.size()-1;
	if (par[u] != -1 && bigch[par[u]] == u) {
		chainhead[u] = chainhead[par[u]];
	}
	else chainhead[u] = u;

	if (debug) cout << "dfs: " << u << " has head "  << chainhead[u] << endl;

	chainend[chainhead[u]] = u; //now I am the smallest

	if (bigch[u]) {
		dfs(bigch[u]);
	}
	for (int v : adj[u]) {
		if (v != bigch[u] && v != par[u]) {
			dfs(v);
		}
	}
}

void buildtree(int ss = 1, int se = n, int si = 0) {
	//pretty sure this is a useless method

	if (ss == se) {
		seg[si].v[0][0] = seg[si].v[0][1] = seg[si].v[1][0] = seg[si].v[1][1] = inf;
		if (mycol[preorder[ss]] != 1) seg[si].v[1][1] = 0 + ccost[preorder[ss]][1];
		if (mycol[preorder[ss]] != 2) seg[si].v[0][0] = 0 + ccost[preorder[ss]][0];
		return;
	}

	int mid = (ss+se)/2;
	buildtree(ss, mid, si*2+1);
	buildtree(mid+1, se, si*2+2);
	seg[si] = merge(seg[si*2+1], seg[si*2+2]);
}

void upd(int spot, int ss = 1, int se = n, int si = 0) {
	if (ss == se) {
		//update explicitly
		seg[si].v[0][0] = seg[si].v[0][1] = seg[si].v[1][0] = seg[si].v[1][1] = inf;
		if (mycol[preorder[ss]] != 1) seg[si].v[1][1] = 0 + ccost[preorder[ss]][1];
		if (mycol[preorder[ss]] != 2) seg[si].v[0][0] = 0 + ccost[preorder[ss]][0];
		
		if (debug) {
			cout << "updating " << spot << endl;
			cout << "    "; printmat(seg[si]);
		}

		return;
	}
	int mid = (ss+se)/2;
	if (spot <= mid) upd(spot, ss, mid, si*2+1);
	else upd(spot, mid+1, se, si*2+2);
	seg[si] = merge(seg[si*2+1], seg[si*2+2]);
}

mat zs; //zeroes

mat query(int qs, int qe, int ss = 1, int se = n, int si = 0) {
	if (qs > qe || ss > se || qs > se || qe < ss) return zs;
	if (qs <= ss && se <= qe) {
		return seg[si];
	}
	int mid = (ss+se)/2;

	if (qs > mid) {
		return query(qs, qe, mid+1, se, si*2+2);
	}
	if (qe <= mid) {
		return query(qs, qe, ss, mid, si*2+1);
	}

	mat lhs = query(qs, qe, ss, mid, si*2+1);
	mat rhs = query(qs, qe, mid+1, se, si*2+2);
	
	return merge(lhs, rhs);	
}

int uph(int u) {
	//update up the HLD structure
	// if (debug) cout << "start of an HLD trek: ";

	while (true) { //should return eventually
		int nx = chainhead[u];


		// cout << u << " goes to " << nx << endl;

		upd(myspot[u]);

		if (debug) {
			cout << "      " << u << " :: " << ccost[u][0] << " - " << ccost[u][1] << endl;
			mat cccc = query(myspot[u], myspot[u]);
			cout << "     "; printmat(cccc) ;	
		}

		mat cv = query(myspot[nx], myspot[chainend[nx]]);
		int c0 = min(cv.v[0][0], cv.v[0][1]);
		int c1 = min(cv.v[1][0], cv.v[1][1]);

		// if (debug) cout << u << " ";

		if (nx == 1) {

			// cout << "THING THING: ";
			// printmat(cv);
			// if (debug) cout << 1 << endl;
			if (debug) cout  << c0 << " VVVVV  " << c1 << endl;
			// if (debug) cout << "CCOSTS: " << ccost[1][0] << " -- " << ccost[1][1] << endl;

			return min(c0, c1);
		}	
		// if (debug) cout << "   at " << u << " with " << c0 << " and " << c1 << endl;
		// if (debug) {
		// 	cout << "       ";
		// 	printmat(cv);
		// }
		int op = par[nx];
		ccost[op][0] += min(c0, c1 + 1) - min(pardiff[nx][0], pardiff[nx][1] + 1);
		ccost[op][1] += min(c1, c0 + 1) - min(pardiff[nx][1], pardiff[nx][0] + 1);
		pardiff[nx][0] = c0;
		pardiff[nx][1] = c1;
		u = op;
	}


}

void initialize(int N, vector<int> A, vector<int> B) {
	n = N;

	for (int i = 0; i < N-1; i++) {
		adj[A[i]].push_back(B[i]);
		adj[B[i]].push_back(A[i]);
	}

	par[1] = -1;
	preorder.push_back(-1); //just buffer it so I can one-index
	predfs(1);
	dfs(1); //this is to get the preorder
	buildtree(); //do not need this because the answer is
	zs.v[0][1] = zs.v[1][0] = inf;

	// cout << "DONE WITH INIT" << endl;
}

int cat(int v) {
	if (debug) cout << "CAT at " << v  << endl;
	mycol[v] = 1;
 	return uph(v);
}

int dog(int v) {
	if (debug) cout << "DOG at " << v << endl;
	mycol[v] = 2;

	if (debug) uph(v);

	if (debug) {
		for (int i = 1; i <= n; i++) {
			cout << i << " ::: ";
			mat cc = query(myspot[i], myspot[i]);
			printmat(cc);
		}
	}

	return uph(v);

}

int neighbor(int v) {
	if (debug) cout << "EMPTY at " << v << endl;
	mycol[v] = 0;
	return uph(v);
}
//THIS IS DONE IN THE WEIRD IOI STYLE
//MUST BE DONE ONLINE
//let's do the HLD thing where ranges are consecutive in a single segment tree

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2680 KB Output is correct
2 Correct 3 ms 2680 KB Output is correct
3 Correct 3 ms 2680 KB Output is correct
4 Correct 3 ms 2680 KB Output is correct
5 Correct 4 ms 2680 KB Output is correct
6 Correct 3 ms 2808 KB Output is correct
7 Correct 3 ms 2680 KB Output is correct
8 Correct 3 ms 2680 KB Output is correct
9 Correct 3 ms 2680 KB Output is correct
10 Correct 3 ms 2808 KB Output is correct
11 Correct 3 ms 2680 KB Output is correct
12 Correct 3 ms 2680 KB Output is correct
13 Correct 3 ms 2680 KB Output is correct
14 Correct 3 ms 2680 KB Output is correct
15 Correct 3 ms 2764 KB Output is correct
16 Correct 3 ms 2684 KB Output is correct

Subtask #2
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2680 KB Output is correct
2 Correct 3 ms 2680 KB Output is correct
3 Correct 3 ms 2680 KB Output is correct
4 Correct 3 ms 2680 KB Output is correct
5 Correct 4 ms 2680 KB Output is correct
6 Correct 3 ms 2808 KB Output is correct
7 Correct 3 ms 2680 KB Output is correct
8 Correct 3 ms 2680 KB Output is correct
9 Correct 3 ms 2680 KB Output is correct
10 Correct 3 ms 2808 KB Output is correct
11 Correct 3 ms 2680 KB Output is correct
12 Correct 3 ms 2680 KB Output is correct
13 Correct 3 ms 2680 KB Output is correct
14 Correct 3 ms 2680 KB Output is correct
15 Correct 3 ms 2764 KB Output is correct
16 Correct 3 ms 2684 KB Output is correct
17 Correct 4 ms 2808 KB Output is correct
18 Correct 5 ms 2808 KB Output is correct
19 Correct 5 ms 2936 KB Output is correct
20 Correct 4 ms 2808 KB Output is correct
21 Correct 4 ms 2808 KB Output is correct
22 Correct 4 ms 2808 KB Output is correct
23 Correct 6 ms 2808 KB Output is correct
24 Correct 5 ms 2808 KB Output is correct
25 Correct 5 ms 2808 KB Output is correct
26 Correct 4 ms 2808 KB Output is correct
27 Correct 5 ms 2808 KB Output is correct
28 Correct 4 ms 2808 KB Output is correct
29 Correct 5 ms 2936 KB Output is correct
30 Correct 4 ms 2808 KB Output is correct
31 Correct 4 ms 2808 KB Output is correct
32 Correct 5 ms 2808 KB Output is correct

Subtask #3
62.0 / 62.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 2680 KB Output is correct
2 Correct 3 ms 2680 KB Output is correct
3 Correct 3 ms 2680 KB Output is correct
4 Correct 3 ms 2680 KB Output is correct
5 Correct 4 ms 2680 KB Output is correct
6 Correct 3 ms 2808 KB Output is correct
7 Correct 3 ms 2680 KB Output is correct
8 Correct 3 ms 2680 KB Output is correct
9 Correct 3 ms 2680 KB Output is correct
10 Correct 3 ms 2808 KB Output is correct
11 Correct 3 ms 2680 KB Output is correct
12 Correct 3 ms 2680 KB Output is correct
13 Correct 3 ms 2680 KB Output is correct
14 Correct 3 ms 2680 KB Output is correct
15 Correct 3 ms 2764 KB Output is correct
16 Correct 3 ms 2684 KB Output is correct
17 Correct 4 ms 2808 KB Output is correct
18 Correct 5 ms 2808 KB Output is correct
19 Correct 5 ms 2936 KB Output is correct
20 Correct 4 ms 2808 KB Output is correct
21 Correct 4 ms 2808 KB Output is correct
22 Correct 4 ms 2808 KB Output is correct
23 Correct 6 ms 2808 KB Output is correct
24 Correct 5 ms 2808 KB Output is correct
25 Correct 5 ms 2808 KB Output is correct
26 Correct 4 ms 2808 KB Output is correct
27 Correct 5 ms 2808 KB Output is correct
28 Correct 4 ms 2808 KB Output is correct
29 Correct 5 ms 2936 KB Output is correct
30 Correct 4 ms 2808 KB Output is correct
31 Correct 4 ms 2808 KB Output is correct
32 Correct 5 ms 2808 KB Output is correct
33 Correct 313 ms 11580 KB Output is correct
34 Correct 123 ms 11636 KB Output is correct
35 Correct 274 ms 9852 KB Output is correct
36 Correct 569 ms 18156 KB Output is correct
37 Correct 25 ms 7032 KB Output is correct
38 Correct 598 ms 19128 KB Output is correct
39 Correct 560 ms 19168 KB Output is correct
40 Correct 566 ms 19132 KB Output is correct
41 Correct 556 ms 19128 KB Output is correct
42 Correct 556 ms 19268 KB Output is correct
43 Correct 589 ms 19168 KB Output is correct
44 Correct 558 ms 19140 KB Output is correct
45 Correct 568 ms 19168 KB Output is correct
46 Correct 578 ms 19148 KB Output is correct
47 Correct 568 ms 19132 KB Output is correct
48 Correct 163 ms 15040 KB Output is correct
49 Correct 195 ms 16928 KB Output is correct
50 Correct 57 ms 6392 KB Output is correct
51 Correct 68 ms 8916 KB Output is correct
52 Correct 28 ms 5880 KB Output is correct
53 Correct 248 ms 17440 KB Output is correct
54 Correct 155 ms 9772 KB Output is correct
55 Correct 460 ms 15884 KB Output is correct
56 Correct 246 ms 10784 KB Output is correct
57 Correct 314 ms 17300 KB Output is correct
58 Correct 36 ms 8748 KB Output is correct
59 Correct 59 ms 7672 KB Output is correct
60 Correct 146 ms 15736 KB Output is correct
61 Correct 166 ms 16460 KB Output is correct
62 Correct 103 ms 14032 KB Output is correct
63 Correct 60 ms 11664 KB Output is correct
64 Correct 70 ms 13044 KB Output is correct
65 Correct 107 ms 19700 KB Output is correct
66 Correct 68 ms 7672 KB Output is correct
67 Correct 89 ms 16112 KB Output is correct
68 Correct 171 ms 20220 KB Output is correct
69 Correct 33 ms 4472 KB Output is correct
70 Correct 10 ms 3064 KB Output is correct
71 Correct 74 ms 11244 KB Output is correct
72 Correct 111 ms 18164 KB Output is correct
73 Correct 230 ms 22848 KB Output is correct
74 Correct 264 ms 20112 KB Output is correct
75 Correct 187 ms 22768 KB Output is correct
76 Correct 173 ms 21748 KB Output is correct
77 Correct 263 ms 20344 KB Output is correct