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Submission #213370

# Submission time Handle Problem Language Result Execution time Memory
213370 2020-03-25T16:20:18 Z Saboon Matching (COCI20_matching) C++14
18 / 110
 334 ms 524292 KB 
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;

const int maxn = 100000 + 10;
const int maxl = 100;

struct point{
	int x, y;
} p[maxn];

struct segment{
	point a;
	point b;
	int i1, i2;
	segment(){
		i1 = i2 = -1;
	}
} s[maxn];

vector<int> vex[maxn], vey[maxn], vec[maxn], add[maxn], del[maxn];
int ask[maxn], cnt;
int lc[maxn * maxl], rc[maxn * maxl];
vector<int> g[maxn * maxl][2];
bool light[maxn][2];
int cmp[maxn * maxl], comp;
bool visited[maxn * maxl];

vector<int> topol;
void dfs(int v, bool w){
	visited[v] = 1;
	for (auto u : g[v][w])
		if (!visited[u])
			dfs(u, w);
	if (w == 0)
		topol.push_back(v);
	else
		cmp[v] = comp;
}

void scc(){
	int n = cnt;
	for (int i = 0; i < n; i++)
		if (!visited[i])
			dfs(i, 0);
	reverse(topol.begin(), topol.end());
	memset(visited, 0, sizeof visited);
	for (auto i : topol){
		if (!visited[i]){
			dfs(i, 1);
			comp ++;
		}
	}
}

void add_edge(int v, int u, bool type){ // type = 0 : v -> u, else v <- u
	if (type == 1)
		swap(v, u);
//	cout << "edge : " << v << " -> " << u << endl;
	g[v][0].push_back(u);
	g[u][1].push_back(v);
}

void get(int id, int L, int R, int l, int r, int v, bool type){
	if (r <= L or R <= l)
		return;
	if (l <= L and R <= r){
		add_edge(v, id, type);
		return;
	}
	int mid = (L + R) >> 1;
	get(lc[id], L, mid, l, r, v, type);
	get(rc[id], mid, R, l, r, v, type);
}

int change(int id, int L, int R, int idx, int v, bool type){
	if (idx < L or R <= idx)
		return id;
	int me = cnt ++;
	if (L + 1 == R){
		if (light[L][type] == 1)
			return me;
		add_edge(me, v, type);
		light[L][type] = 1;
		return me;
	}
	int mid = (L + R) >> 1;
	lc[me] = change(lc[id], L, mid, idx, v, type);
	rc[me] = change(rc[id], mid, R, idx, v, type);
	add_edge(me, lc[me], type), add_edge(me, rc[me], type);
	return me;
}

int build(int L, int R, bool type){
	int me = cnt ++;
	if (L + 1 == R)
		return me;
	int mid = (L + R) >> 1;
	lc[me] = build(L, mid, type);
	rc[me] = build(mid, R, type);
	add_edge(me, lc[me], type), add_edge(me, rc[me], type);
	return me;
}

int main(){
	ios_base::sync_with_stdio(false);
	int n;
	cin >> n;
	for (int i = 0; i < n; i++){
		cin >> p[i].x >> p[i].y;
		vex[p[i].x].push_back(i);
		vey[p[i].y].push_back(i);
	}
	int newint = 0;
	int N = 100000 + 1;
	for (int i = 1; i < N; i++){
		if (vex[i].size() == 2){
			segment me;
			me.a = p[vex[i][0]];
			me.b = p[vex[i][1]];
			me.i1 = vex[i][0];
			me.i2 = vex[i][1];
			vec[me.i1].push_back(newint);
			vec[me.i2].push_back(newint);
			s[newint++] = me;
		}
		if (vey[i].size() == 2){
			segment me;
			me.a = p[vey[i][0]];
			me.b = p[vey[i][1]];
			me.i1 = vey[i][0];
			me.i2 = vey[i][1];
			vec[me.i1].push_back(newint);
			vec[me.i2].push_back(newint);
			s[newint++] = me;
		}
	}
	int m = newint;
	memset(ask, -1, sizeof ask);
	for (int i = 0; i < m; i++){
		if (s[i].a.x != s[i].b.x){
			if (s[i].a.x > s[i].b.x){
				swap(s[i].a, s[i].b);
				swap(s[i].i1, s[i].i2);
			}
			add[s[i].a.x].push_back(i);
			add[s[i].b.x].push_back(i);
		}
		else
			ask[s[i].a.x] = i;
	}
	for (int i = 0; i < n; i++){
		if ((int)vec[i].size() == 0)
			return cout << "NE\n", 0;
		if ((int)vec[i].size() == 1){
			int v = vec[i][0];
			add_edge(2*v+1, 2*v+0, 0);
			continue;
		}
		int v = vec[i][0], u = vec[i][1];
		add_edge(2*v+1, 2*u+0, 0);
		add_edge(2*u+1, 2*v+0, 0);
		add_edge(2*v+0, 2*u+1, 0);
		add_edge(2*u+0, 2*v+1, 0);
	}
//	for (int i = 0; i < m; i++)
//		cout << "# " << i << " -> (" << s[i].a.x << " , " << s[i].a.y << ") - (" << s[i].b.x << " , " << s[i].b.y << ")" << endl; 
	cnt = 2*m;
	int r1 = build(1, N, 0);
	int r2 = build(1, N, 1);
	for (int i = 1; i < N; i++){
		if (ask[i] != -1){
			int idx = ask[i];
			int y1 = s[idx].a.y, y2 = s[idx].b.y;
			if (y1 > y2)
				swap(y1, y2);
			get(r1, 1, N, y1+1, y2, 2*idx+0, 0);
			get(r2, 1, N, y1+1, y2, 2*idx+1, 1);
//			cout << "Ask : " << idx << " : " << y1+1 << " - " << y2 << endl;
		}
		for (auto idx : add[i]){
//			cout << "Add or Remove : " << idx << " - " << s[idx].a.y << endl;
			r1 = change(r1, 1, N, s[idx].a.y, 2*idx+1, 0);
			r2 = change(r2, 1, N, s[idx].a.y, 2*idx+0, 1);
		}
	}
	scc();
	for (int i = 0; i < 2*m; i+=2)
		if (cmp[i] == cmp[i+1])
			return cout << "NE\n", 0;
	cout << "DA\n";
	for (int i = 0; i < m; i++)
		if (cmp[2*i+0] > cmp[2*i+1])
			cout << s[i].i1 + 1 << " " << s[i].i2 + 1 << '\n';
}

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 334 ms 519524 KB Output is correct
2 Correct 315 ms 519652 KB Output is correct

Subtask #2
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 334 ms 519524 KB Output is correct
2 Correct 315 ms 519652 KB Output is correct
3 Correct 312 ms 519660 KB Output is correct
4 Correct 318 ms 519656 KB Output is correct
5 Correct 314 ms 519656 KB Output is correct
6 Correct 318 ms 519648 KB Output is correct
7 Correct 317 ms 519652 KB Output is correct

Subtask #3
7.0 / 7.0

# Verdict Execution time Memory Grader output
1 Correct 334 ms 519524 KB Output is correct
2 Correct 315 ms 519652 KB Output is correct
3 Correct 312 ms 519660 KB Output is correct
4 Correct 318 ms 519656 KB Output is correct
5 Correct 314 ms 519656 KB Output is correct
6 Correct 318 ms 519648 KB Output is correct
7 Correct 317 ms 519652 KB Output is correct
8 Correct 321 ms 519784 KB Output is correct
9 Correct 311 ms 519788 KB Output is correct
10 Correct 320 ms 519784 KB Output is correct
11 Correct 312 ms 519784 KB Output is correct
12 Correct 311 ms 519784 KB Output is correct

Subtask #4
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 334 ms 519524 KB Output is correct
2 Correct 315 ms 519652 KB Output is correct
3 Correct 312 ms 519660 KB Output is correct
4 Correct 318 ms 519656 KB Output is correct
5 Correct 314 ms 519656 KB Output is correct
6 Correct 318 ms 519648 KB Output is correct
7 Correct 317 ms 519652 KB Output is correct
8 Correct 321 ms 519784 KB Output is correct
9 Correct 311 ms 519788 KB Output is correct
10 Correct 320 ms 519784 KB Output is correct
11 Correct 312 ms 519784 KB Output is correct
12 Correct 311 ms 519784 KB Output is correct
13 Runtime error 295 ms 524292 KB Execution killed with signal 9 (could be triggered by violating memory limits)
14 Halted 0 ms 0 KB -

Subtask #5
0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 334 ms 519524 KB Output is correct
2 Correct 315 ms 519652 KB Output is correct
3 Correct 312 ms 519660 KB Output is correct
4 Correct 318 ms 519656 KB Output is correct
5 Correct 314 ms 519656 KB Output is correct
6 Correct 318 ms 519648 KB Output is correct
7 Correct 317 ms 519652 KB Output is correct
8 Correct 321 ms 519784 KB Output is correct
9 Correct 311 ms 519788 KB Output is correct
10 Correct 320 ms 519784 KB Output is correct
11 Correct 312 ms 519784 KB Output is correct
12 Correct 311 ms 519784 KB Output is correct
13 Runtime error 295 ms 524292 KB Execution killed with signal 9 (could be triggered by violating memory limits)
14 Halted 0 ms 0 KB -