Submission #223426

#	Time	Username	Problem	Language	Result	Execution time	Memory
223426		shenxy	Matching (COCI20_matching)	C++11	58 / 110	1790 ms	524292 KiB

matching

#include <cstdio>
#include <algorithm>
#include <queue>
using namespace std;
typedef pair<int, int> ii;
typedef pair<ii, int> iii;
const int INF = 10000000;
struct minseg {
	int s, e, m;
	ii v;
	minseg *l, *r;
	minseg(int _s, int _e) {
		s = _s, e = _e, m = (s + e) / 2;
		v = ii(INF, -1);
		l = r = NULL;
	}
	void update(int i, ii nv) {
		if (s != e) {
			if (i > m) {
				if (r == NULL) r = new minseg(m + 1, e);
				r -> update(i, nv);
			} else {
				if (l == NULL) l = new minseg(s, m);
				l -> update(i, nv);
			}
			v = min(l == NULL ? ii(INF, -1) : l -> v, r == NULL ? ii(INF, -1) : r -> v);
		} else v = nv;
	}
	ii query(int a, int b) {
		if (s == a && e == b) return v;
		if (a > m) return r == NULL ? ii(INF, -1) : r -> query(a, b);
		if (b <= m) return l == NULL ? ii(INF, -1) : l -> query(a, b);
		return min(l == NULL ? ii(INF, -1) : l -> query(a, m), r == NULL ? ii(INF, -1) : r -> query(m + 1, b));
	}
};
struct minseg2d {
	int s, e, m;
	minseg *v;
	minseg2d *l, *r;
	minseg2d(int rs, int re, int cs, int ce) {
		s = rs, e = re, m = (s + e) / 2;
		v = new minseg(cs, ce);
		l = r = NULL;
	}
	void update(int R, int C, ii nv) {
		if (s != e) {
			if (R > m) {
				if (r == NULL) r = new minseg2d(m + 1, e, v -> s, v -> e);
				r -> update(R, C, nv);
			} else {
				if (l == NULL) l = new minseg2d(s, m, v -> s, v -> e);
				l -> update(R, C, nv);
			}
			v -> update(C, min(l == NULL ? ii(INF, -1) : l -> v -> query(C, C), r == NULL ? ii(INF, -1) : r -> v -> query(C, C)));
		} else v -> update(C, nv);
	}
	ii query(int rs, int re, int cs, int ce) {
		if (s == rs && e == re) return v -> query(cs, ce);
		if (rs > m) return r == NULL ? ii(INF, -1) : r -> query(rs, re, cs, ce);
		if (re <= m) return l == NULL ? ii(INF, -1) : l -> query(rs, re, cs, ce);
		return min(l == NULL ? ii(INF, -1) : l -> query(rs, m, cs, ce), r == NULL ? ii(INF, -1) : r -> query(m + 1, re, cs, ce));
	}
};
struct maxseg {
	int s, e, m;
	ii v;
	maxseg *l, *r;
	maxseg(int _s, int _e) {
		s = _s, e = _e, m = (s + e) / 2;
		v = ii(0, -1);
		l = r = NULL;
	}
	void update(int i, ii nv) {
		if (s != e) {
			if (i > m) {
				if (r == NULL) r = new maxseg(m + 1, e);
				r -> update(i, nv);
			} else {
				if (l == NULL) l = new maxseg(s, m);
				l -> update(i, nv);
			}
			v = max(l == NULL ? ii(0, -1) : l -> v, r == NULL ? ii(0, -1) : r -> v);
		} else v = nv;
	}
	ii query(int a, int b) {
		if (s == a && e == b) return v;
		if (a > m) return r == NULL ? ii(0, -1) : r -> query(a, b);
		if (b <= m) return l == NULL ? ii(0, -1) : l -> query(a, b);
		return max(l == NULL ? ii(0, -1) : l -> query(a, m), r == NULL ? ii(0, -1) : r -> query(m + 1, b));
	}
};
struct maxseg2d {
	int s, e, m;
	maxseg *v;
	maxseg2d *l, *r;
	maxseg2d(int rs, int re, int cs, int ce) {
		s = rs, e = re, m = (s + e) / 2;
		v = new maxseg(cs, ce);
		l = r = NULL;
	}
	void update(int R, int C, ii nv) {
		if (s != e) {
			if (R > m) {
				if (r == NULL) r = new maxseg2d(m + 1, e, v -> s, v -> e);
				r -> update(R, C, nv);
			} else {
				if (l == NULL) l = new maxseg2d(s, m, v -> s, v -> e);
				l -> update(R, C, nv);
			}
			v -> update(C, max(l == NULL ? ii(0, -1) : l -> v -> query(C, C), r == NULL ? ii(0, -1) : r -> v -> query(C, C)));
		} else v -> update(C, nv);
	}
	ii query(int rs, int re, int cs, int ce) {
		if (s == rs && e == re) return v -> query(cs, ce);
		if (rs > m) return r == NULL ? ii(0, -1) : r -> query(rs, re, cs, ce);
		if (re <= m) return l == NULL ? ii(0, -1) : l -> query(rs, re, cs, ce);
		return max(l == NULL ? ii(0, -1) : l -> query(rs, m, cs, ce), r == NULL ? ii(0, -1) : r -> query(m + 1, re, cs, ce));
	}
};
bool comp(const iii &a, const iii &b) {
	if (a.first.second != b.first.second) return a.first.second < b.first.second;
	return a < b;
}
int main() {
	int N;
	scanf("%d", &N);
	iii xy[N];
	ii pos[N];
	minseg2d *minx = new minseg2d(1, 100000, 1, 100000), *miny = new minseg2d(1, 100000, 1, 100000);
	maxseg2d *maxx = new maxseg2d(1, 100000, 1, 100000), *maxy = new maxseg2d(1, 100000, 1, 100000);
	for (int i = 0; i < N; ++i) scanf("%d %d", &pos[i].first, &pos[i].second), xy[i].first = pos[i], xy[i].second = i;
	sort(xy, xy + N);
	int xf[N], yf[N];
	xf[xy[0].second] = -1;
	for (int i = 1; i < N; ++i) {
		if (xy[i - 1].first.first == xy[i].first.first) xf[xy[i - 1].second] = xy[i].second, xf[xy[i].second] = xy[i - 1].second;
		else xf[xy[i].second] = -1;
	}
	sort(xy, xy + N, comp);
	yf[xy[0].second] = -1;
	for (int i = 1; i < N; ++i) {
		if (xy[i - 1].first.second == xy[i].first.second) yf[xy[i - 1].second] = xy[i].second, yf[xy[i].second] = xy[i - 1].second;
		else yf[xy[i].second] = -1;
	}
	queue<int> despo;
	for (int i = 0; i < N; ++i) {
		if (xf[i] == -1 && yf[i] == -1) {
			printf("NE");
			return 0;
		} else if (xf[i] == -1 || yf[i] == -1) despo.push(i);
		if (xf[i] != -1) minx -> update(pos[i].first, pos[i].second, ii(pos[xf[i]].second, i)), maxx -> update(pos[i].first, pos[i].second, ii(pos[xf[i]].second, i));
		if (yf[i] != -1) miny -> update(pos[i].first, pos[i].second, ii(pos[yf[i]].first, i)), maxy -> update(pos[i].first, pos[i].second, ii(pos[yf[i]].first, i));
	}
	vector<ii> pairs;
	bool settled[N];
	fill_n(settled, N, false);
	while (!despo.empty()) {
		int pt1 = despo.front(), pt2;
		despo.pop();
		if (settled[pt1]) continue;
		if (xf[pt1] != -1) {
			pt2 = xf[pt1];
			minx -> update(pos[pt1].first, pos[pt1].second, ii(INF, -1)), maxx -> update(pos[pt1].first, pos[pt1].second, ii(0, -1));
			minx -> update(pos[pt2].first, pos[pt2].second, ii(INF, -1)), maxx -> update(pos[pt2].first, pos[pt2].second, ii(0, -1));
			if (yf[pt2] != -1) {
				miny -> update(pos[pt2].first, pos[pt2].second, ii(INF, -1)), maxy -> update(pos[pt2].first, pos[pt2].second, ii(0, -1));
				miny -> update(pos[yf[pt2]].first, pos[yf[pt2]].second, ii(INF, -1)), maxy -> update(pos[yf[pt2]].first, pos[yf[pt2]].second, ii(0, -1));
				yf[yf[pt2]] = -1;
				if (xf[yf[pt2]] == -1) {
					printf("NE");
					return 0;
				} else despo.push(yf[pt2]);
			}
			ii qans = maxy -> query(1, pos[pt1].first - 1, min(pos[pt1].second, pos[pt2].second), max(pos[pt1].second, pos[pt2].second));
			while (qans.first > pos[pt1].first) {
				miny -> update(pos[qans.second].first, pos[qans.second].second, ii(INF, -1)), maxy -> update(pos[qans.second].first, pos[qans.second].second, ii(0, -1));
				yf[qans.second] = -1;
				if (xf[qans.second] == -1) {
					printf("NE");
					return 0;
				} else despo.push(qans.second);
				qans = maxy -> query(1, pos[pt1].first - 1, min(pos[pt1].second, pos[pt2].second), max(pos[pt1].second, pos[pt2].second));
			}
			qans = miny -> query(pos[pt1].first + 1, 100000, min(pos[pt1].second, pos[pt2].second), max(pos[pt1].second, pos[pt2].second));
			while (qans.first < pos[pt1].first) {
				miny -> update(pos[qans.second].first, pos[qans.second].second, ii(INF, -1)), maxy -> update(pos[qans.second].first, pos[qans.second].second, ii(0, -1));
				yf[qans.second] = -1;
				if (xf[qans.second] == -1) {
					printf("NE");
					return 0;
				} else despo.push(qans.second);
				qans = miny -> query(pos[pt1].first + 1, 100000, min(pos[pt1].second, pos[pt2].second), max(pos[pt1].second, pos[pt2].second));
			}
		} else {
			pt2 = yf[pt1];
			miny -> update(pos[pt1].first, pos[pt1].second, ii(INF, -1)), maxy -> update(pos[pt1].first, pos[pt1].second, ii(0, -1));
			miny -> update(pos[pt2].first, pos[pt2].second, ii(INF, -1)), maxy -> update(pos[pt2].first, pos[pt2].second, ii(0, -1));
			if (xf[pt2] != -1) {
				minx -> update(pos[pt2].first, pos[pt2].second, ii(INF, -1)), maxx -> update(pos[pt2].first, pos[pt2].second, ii(0, -1));
				minx -> update(pos[xf[pt2]].first, pos[xf[pt2]].second, ii(INF, -1)), maxx -> update(pos[xf[pt2]].first, pos[xf[pt2]].second, ii(0, -1));
				xf[xf[pt2]] = -1;
				if (yf[xf[pt2]] == -1) {
					printf("NE");
					return 0;
				} else despo.push(xf[pt2]);
			}
			ii qans = maxx -> query(min(pos[pt1].first, pos[pt2].first), max(pos[pt1].first, pos[pt2].first), 1, pos[pt1].second - 1);
			while (qans.first > pos[pt1].second) {
				minx -> update(pos[qans.second].first, pos[qans.second].second, ii(INF, -1)), maxx -> update(pos[qans.second].first, pos[qans.second].second, ii(0, -1));
				xf[qans.second] = -1;
				if (yf[qans.second] == -1) {
					printf("NE");
					return 0;
				} else despo.push(qans.second);
				qans = maxx -> query(min(pos[pt1].first, pos[pt2].first), max(pos[pt1].first, pos[pt2].first), 1, pos[pt1].second - 1);
			}
			qans = minx -> query(min(pos[pt1].first, pos[pt2].first), max(pos[pt1].first, pos[pt2].first), pos[pt1].second + 1, 100000);
			while (qans.first < pos[pt1].second) {
				minx -> update(pos[qans.second].first, pos[qans.second].second, ii(INF, -1)), maxx -> update(pos[qans.second].first, pos[qans.second].second, ii(0, -1));
				xf[qans.second] = -1;
				if (yf[qans.second] == -1) {
					printf("NE");
					return 0;
				} else despo.push(qans.second);
				qans = minx -> query(min(pos[pt1].first, pos[pt2].first), max(pos[pt1].first, pos[pt2].first), pos[pt1].second + 1, 100000);
			}
		}
		pairs.push_back(ii(pt1, pt2));
		settled[pt1] = settled[pt2] = true;
	}
	for (int i = 0; i < N; ++i) {
		if (!settled[i]) pairs.push_back(ii(i, xf[i])), settled[i] = settled[xf[i]] = true;
	}
	printf("DA\n");
	for (ii i: pairs) printf("%d %d\n", i.first + 1, i.second + 1);
}

Compilation message (stderr)

matching.cpp: In function 'int main()':
matching.cpp:126:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d", &N);
  ~~~~~^~~~~~~~~~
matching.cpp:131:97: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for (int i = 0; i < N; ++i) scanf("%d %d", &pos[i].first, &pos[i].second), xy[i].first = pos[i], xy[i].second = i;
                              ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~
matching.cpp:155:7: warning: argument 1 range [18446744071562067968, 18446744073709551615] exceeds maximum object size 9223372036854775807 [-Walloc-size-larger-than=]
  bool settled[N];
       ^~~~~~~
matching.cpp:155:7: note: in a call to built-in allocation function 'void* __builtin_alloca_with_align(long unsigned int, long unsigned int)'

• Subtask 1: 5 / 5
• Subtask 2: 6 / 6
• Subtask 3: 7 / 7
• Subtask 4: 40 / 40
• Subtask 5: 0 / 52