Submission #774572

#	Time	Username	Problem	Language	Result	Execution time	Memory
774572		rainboy	Phone Plans (CCO22_day2problem2)	C11	25 / 25	727 ms	106944 KiB

Main

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define N	200000
#define M	200000
#define N_	(N * 4)
#define MD	0x7fffffff

int min(int a, int b) { return a < b ? a : b; }

unsigned int Z = 12345;

int rand_() {
	return (Z *= 3) >> 1;
}

long long cnt;

long long *ek[N_]; int *ev[N_], eo[N_], eo_[N_], X = 123456789;

void init() {
	int h;

	for (h = 0; h < N_; h++) {
		eo_[h] = 2;
		ek[h] = (long long *) malloc(eo_[h] * sizeof *ek[h]);
		ev[h] = (int *) malloc(eo_[h] * sizeof *ev[h]);
	}
}

int hash(long long k) {
	int k1 = k / MD, k2 = k % MD;

	return ((long long) k1 * X % MD + k2) % MD * X % MD % N_;
}

void put(long long k, int v) {
	int h = hash(k), o;

	for (o = eo[h]; o--; )
		if (ek[h][o] == k) {
			int v_ = ev[h][o];

			cnt += (long long) v_ * (v_ - 1) / 2;
			v_ += v;
			cnt -= (long long) v_ * (v_ - 1) / 2;
			if (v_ == 0) {
				eo[h]--;
				while (o < eo[h])
					ek[h][o] = ek[h][o + 1], ev[h][o] = ev[h][o + 1], o++;
			} else
				ev[h][o] = v_;
			return;
		}
	o = eo[h]++;
	if (o == eo_[h]) {
		eo_[h] *= 2;
		ek[h] = (long long *) realloc(ek[h], eo_[h] * sizeof *ek[h]);
		ev[h] = (int *) realloc(ev[h], eo_[h] * sizeof *ev[h]);
	}
	ek[h][o] = k, ev[h][o] = v;
	cnt -= (long long) v * (v - 1) / 2;
}

int n;

int ddx[N], ddy[N];

void add(int x, int y, int v) {
	cnt -= (long long) ddx[x] * (ddx[x] - 1) / 2, ddx[x] += v, cnt += (long long) ddx[x] * (ddx[x] - 1) / 2;
	cnt -= (long long) ddy[y] * (ddy[y] - 1) / 2, ddy[y] += v, cnt += (long long) ddy[y] * (ddy[y] - 1) / 2;
	put((long long) x * n + y, v);
}

int *ww;

void sort(int *hh, int l, int r) {
	while (l < r) {
		int i = l, j = l, k = r, h = hh[l + rand_() % (r - l)], tmp;

		while (j < k)
			if (ww[hh[j]] == ww[h])
				j++;
			else if (ww[hh[j]] < ww[h]) {
				tmp = hh[i], hh[i] = hh[j], hh[j] = tmp;
				i++, j++;
			} else {
				k--;
				tmp = hh[j], hh[j] = hh[k], hh[k] = tmp;
			}
		sort(hh, l, i);
		l = k;
	}
}

int ds[N];

int find(int i) {
	return ds[i] < 0 ? i : (ds[i] = find(ds[i]));
}

void append(int **ej, int *eo, int i, int j) {
	int o = eo[i]++;

	if (o >= 2 && (o & o - 1) == 0)
		ej[i] = (int *) realloc(ej[i], o * 2 * sizeof *ej[i]);
	ej[i][o] = j;
}

int *ej1[N], eo1[N], *ej2[N], eo2[N], xx[N], yy[N];

void dfs1(int i, int x) {
	int o;

	add(xx[i], yy[i], -1), xx[i] = x, add(xx[i], yy[i], 1);
	for (o = eo1[i]; o--; ) {
		int j = ej1[i][o];

		dfs1(j, x);
	}
}

void dfs2(int i, int y) {
	int o;

	add(xx[i], yy[i], -1), yy[i] = y, add(xx[i], yy[i], 1);
	for (o = eo2[i]; o--; ) {
		int j = ej2[i][o];

		dfs2(j, y);
	}
}

int main() {
	static int ii1[M], jj1[M], ww1[M], hh1[M], ii2[M], jj2[M], ww2[M], hh2[M];
	int m1, m1_, m2, m2_, h, h1, h2, i, j, tmp, ans;
	long long cnt_;

	init();
	scanf("%d%d%d%lld", &n, &m1, &m2, &cnt_);
	for (h = 0; h < m1; h++)
		scanf("%d%d%d", &ii1[h], &jj1[h], &ww1[h]), ii1[h]--, jj1[h]--;
	for (h = 0; h < m2; h++)
		scanf("%d%d%d", &ii2[h], &jj2[h], &ww2[h]), ii2[h]--, jj2[h]--;
	for (h = 0; h < m1; h++)
		hh1[h] = h;
	ww = ww1, sort(hh1, 0, m1);
	memset(ds, -1, n * sizeof *ds);
	for (i = 0; i < n; i++)
		ej1[i] = (int *) malloc(2 * sizeof *ej1[i]);
	m1_ = 0;
	for (h = 0; h < m1; h++) {
		h1 = hh1[h], i = find(ii1[h1]), j = find(jj1[h1]);
		if (i == j)
			continue;
		if (ds[i] > ds[j])
			tmp = i, i = j, j = tmp;
		if (ds[i] == ds[j])
			ds[i]--;
		ds[j] = i, append(ej1, eo1, i, j);
		ii1[h1] = i, jj1[h1] = j, hh1[m1_++] = h1;
	}
	m1 = m1_;
	for (h = 0; h < m2; h++)
		hh2[h] = h;
	ww = ww2, sort(hh2, 0, m2);
	memset(ds, -1, n * sizeof *ds);
	for (i = 0; i < n; i++)
		ej2[i] = (int *) malloc(2 * sizeof *ej2[i]);
	m2_ = 0;
	for (h = 0; h < m2; h++) {
		h2 = hh2[h], i = find(ii2[h2]), j = find(jj2[h2]);
		if (i == j)
			continue;
		if (ds[i] > ds[j])
			tmp = i, i = j, j = tmp;
		if (ds[i] == ds[j])
			ds[i]--;
		ds[j] = i, append(ej2, eo2, i, j);
		ii2[h2] = i, jj2[h2] = j, hh2[m2_++] = h2;
	}
	m2 = m2_;
	for (i = 0; i < n; i++) {
		xx[i] = i, yy[i] = find(i);
		add(xx[i], yy[i], 1);
	}
	ans = MD;
	for (h1 = -1, h2 = m2 - 1; h1 < m1; h1++) {
		if (h1 >= 0)
			dfs1(jj1[hh1[h1]], ii1[hh1[h1]]);
		while (h2 >= -1 && cnt >= cnt_) {
			ans = min(ans, (h1 < 0 ? 0 : ww1[hh1[h1]]) + (h2 < 0 ? 0 : ww2[hh2[h2]]));
			if (h2 >= 0)
				dfs2(jj2[hh2[h2]], jj2[hh2[h2]]);
			h2--;
		}
	}
	if (ans == MD)
		ans = -1;
	printf("%d\n", ans);
	return 0;
}

Compilation message (stderr)

Main.c: In function 'append':
Main.c:106:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
  106 |  if (o >= 2 && (o & o - 1) == 0)
      |                     ~~^~~
Main.c: In function 'main':
Main.c:141:2: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  141 |  scanf("%d%d%d%lld", &n, &m1, &m2, &cnt_);
      |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.c:143:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  143 |   scanf("%d%d%d", &ii1[h], &jj1[h], &ww1[h]), ii1[h]--, jj1[h]--;
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.c:145:3: warning: ignoring return value of 'scanf' declared with attribute 'warn_unused_result' [-Wunused-result]
  145 |   scanf("%d%d%d", &ii2[h], &jj2[h], &ww2[h]), ii2[h]--, jj2[h]--;
      |   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 5 / 5
• Subtask 3: 6 / 6
• Subtask 4: 8 / 8