Submission #758443

#	Time	Username	Problem	Language	Result	Execution time	Memory
758443		rainboy	Cyberland (APIO23_cyberland)	C++17	100 / 100	2363 ms	14008 KiB

cyberland

#include "cyberland.h"
#include <cstdlib>
#include <vector>

using namespace std;

typedef vector<int> vi;

const int N = 100000, K = 120;
const double INF = 1e18;

int *ej[N], *ew[N], eo[N];

void append(int i, int j, int w) {
	int o = eo[i]++;
	if (o >= 2 && (o & o - 1) == 0) {
		ej[i] = (int *) realloc(ej[i], o * 2 * sizeof *ej[i]);
		ew[i] = (int *) realloc(ew[i], o * 2 * sizeof *ew[i]);
	}
	ej[i][o] = j, ew[i][o] = w;
}

double dd[N], dd_[N]; int iq[N + 1], pq[N], cnt;

int lt(int i, int j) { return dd[i] < dd[j]; }

int p2(int p) {
	return (p *= 2) > cnt ? 0 : (p < cnt && lt(iq[p + 1], iq[p]) ? p + 1 : p);
}

void pq_up(int i) {
	int p, q, j;
	for (p = pq[i]; (q = p / 2) && lt(i, j = iq[q]); p = q)
		iq[pq[j] = p] = j;
	iq[pq[i] = p] = i;
}

void pq_dn(int i) {
	int p, q, j;
	for (p = pq[i]; (q = p2(p)) && lt(j = iq[q], i); p = q)
		iq[pq[j] = p] = j;
	iq[pq[i] = p] = i;
}

void pq_add_last(int i) {
	iq[pq[i] = ++cnt] = i;
}

int pq_remove_first() {
	int i = iq[1], j = iq[cnt--];
	if (j != i)
		pq[j] = 1, pq_dn(j);
	pq[i] = 0;
	return i;
}

void dijkstra(int n) {
	for (int i = 0; i < n; i++)
		pq_add_last(i);
	for (int h = cnt / 2; h > 0; h--)
		pq_dn(iq[h]);
	while (cnt) {
		int i = pq_remove_first();
		for (int o = eo[i]; o--; ) {
			int j = ej[i][o], w = ew[i][o];
			double d = dd[i] + w;
			if (dd[j] > d)
				dd[j] = d, pq_up(j);
		}
	}
}

double solve(int n, int m, int k, int t, vi ii, vi jj, vi ww, vi type) {
	type[0] = 0;
	for (int i = 0; i < n; i++) {
		ej[i] = (int *) malloc(2 * sizeof *ej[i]);
		ew[i] = (int *) malloc(2 * sizeof *ew[i]);
		eo[i] = 0;
	}
	for (int h = 0; h < m; h++) {
		int i = ii[h], j = jj[h], w = ww[h];
		if (i != t)
			append(i, j, w);
		if (j != t)
			append(j, i, w);
	}
	for (int i = 0; i < n; i++)
		dd[i] = INF;
	dd[0] = 0;
	dijkstra(n);
	for (int i = 0; i < n; i++)
		dd[i] = type[i] == 0 && dd[i] != INF ? 0 : INF;
	dijkstra(n);
	k = min(k, K);
	while (k--) {
		for (int i = 0; i < n; i++)
			dd_[i] = dd[i];
		for (int i = 0; i < n; i++)
			if (type[i] == 2)
				dd[i] = INF;
		for (int i = 0; i < n; i++)
			if (type[i] == 2 && dd_[i] != INF)
				for (int o = eo[i]; o--; ) {
					int j = ej[i][o], w = ew[i][o];
					dd[j] = min(dd[j], dd_[i] / 2 + w);
				}
		dijkstra(n);
	}
	return dd[t] == INF ? -1 : dd[t];
}

Compilation message (stderr)

cyberland.cpp: In function 'void append(int, int, int)':
cyberland.cpp:16:23: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
   16 |  if (o >= 2 && (o & o - 1) == 0) {
      |                     ~~^~~

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 13 / 13
• Subtask 4: 19 / 19
• Subtask 5: 7 / 7
• Subtask 6: 16 / 16
• Subtask 7: 29 / 29
• Subtask 8: 3 / 3