답안 #680470

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
680470	2023-01-10T23:58:18 Z	kingfran1907	Sailing Race (CEOI12_race)	C++14	100 / 100	2264 ms	6964 KB

race

#include <bits/stdc++.h>
#define X first
#define Y second

using namespace std;
typedef long long llint;

const int maxn = 510;
const int base = 31337;
const int mod = 1e9+7;
const int inf = 0x3f3f3f3f;
const int logo = 20;
const int off = 1 << logo;
const int treesiz = off << 1;

int n, k;
vector< int > graph[maxn], graph2[maxn];
int dp[maxn][maxn][2];
int dist[2][maxn][maxn];
int bes[maxn][maxn][2];

int dis(int x, int y, bool flag = false) {
	if (flag) swap(x, y);
	return (y - x + n) % n;
}

bool check(int l, int r, int x, bool flag = false) {
	if (l == x) return false;
	return dis(l, x, flag) < dis(l, r, flag);
}

int f(int l, int r, bool flag) {
	int &ret = dp[l][r][flag];
	if (ret != -1) return ret;

	ret = 0;
	for (int tren : graph[l]) {
		if (check(l, r, tren, flag)) 
			ret = max(ret, 1 + max(f(tren, l, !flag), f(tren, r, flag)));
	}
	return ret;
}

int main() {
	scanf("%d%d", &n, &k);
	for (int i = 0; i < n; i++) {
		while (true) {
			int x;
			scanf("%d", &x);
			if (x == 0) break;
			graph[i].push_back(x - 1);
			graph2[x - 1].push_back(i);
		}
	}

	pair<int, int> sol = {-1, -1};
	memset(dp, -1, sizeof dp);
	for (int i = 0; i < n; i++) {
		for (int tren : graph[i]) {
			for (int k = 0; k < 2; k++) {
				sol = max(sol, {1 + f(tren, i, k), i});
			}
		}
	}
	if (k == 0) {
		printf("%d\n%d\n", sol.X, sol.Y + 1);
		return 0;
	}

	for (int i = 0; i < n; i++) {
		for (int j = (i + 1) % n; j != i; j++, j %= n) {
			dist[0][i][j] = -inf;
			for (int tren : graph2[j]) {
				if (check(i, j, tren) || tren == i) dist[0][i][j] = max(dist[0][i][j], 1 + dist[0][i][tren]);
			}
		}
		for (int j = (i + n - 1) % n; j != i; j += n - 1, j %= n) {
			dist[1][i][j] = -inf;
			for (int tren : graph2[j]) {
				if (check(i, j, tren, 1) || tren == i) dist[1][i][j] = max(dist[1][i][j], 1 + dist[1][i][tren]);
			}
		}
	}

	memset(bes, -1, sizeof bes);
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			for (int tren : graph2[i]) {
				for (int k = 0; k < 2; k++) {
					if (check(i, j, tren, k)) continue;
					if (bes[i][j][k] == -1) bes[i][j][k] = tren;
					else if (dis(i, tren, k) < dis(i, bes[i][j][k], k)) bes[i][j][k] = tren;
				}
			}
		}
	}

	for (int i = 0; i < n; i++) {
		for (int j = 0; j < n; j++) {
			for (int k = 0; k < 2; k++) {
				if (i == j) continue;
				for (int tren : graph[j]) {
					int tr = bes[i][j][k];
					if (tr == -1) continue;
					if (!check(j, tren, tr, k) || !check(i, j, tren, 1 - k)) continue;

					int ac = dist[k][i][j] + 2 + max(f(tren, tr, 1 - k), f(tren, i, k));
					//printf("%d -> %d -> %d -> %d --- %d (%d)\n", tr, i, j, tren, ac, k);
					//printf("%d + (%d %d)\n", dist[k][i][j], f(tren, tr, 1 - k), f(tren, i, k));
					sol = max(sol, {ac, tr});
				}
			}
		}
	}
	printf("%d\n%d\n", sol.X, sol.Y + 1);
	return 0;
}

Compilation message

race.cpp: In function 'int main()':
race.cpp:45:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   45 |  scanf("%d%d", &n, &k);
      |  ~~~~~^~~~~~~~~~~~~~~~
race.cpp:49:9: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   49 |    scanf("%d", &x);
      |    ~~~~~^~~~~~~~~~

Subtask #1

100.0 / 100.0

#	결과	실행 시간	메모리	Grader output
1	Correct	1 ms	2260 KB	Output is correct
2	Correct	2 ms	4436 KB	Output is correct
3	Correct	2 ms	4436 KB	Output is correct
4	Correct	5 ms	4556 KB	Output is correct
5	Correct	2 ms	2260 KB	Output is correct
6	Correct	7 ms	4652 KB	Output is correct
7	Correct	6 ms	2416 KB	Output is correct
8	Correct	10 ms	4616 KB	Output is correct
9	Correct	8 ms	2388 KB	Output is correct
10	Correct	22 ms	2388 KB	Output is correct
11	Correct	11 ms	2428 KB	Output is correct
12	Correct	147 ms	5256 KB	Output is correct
13	Correct	253 ms	5692 KB	Output is correct
14	Correct	82 ms	2388 KB	Output is correct
15	Correct	1503 ms	6716 KB	Output is correct
16	Correct	1876 ms	6876 KB	Output is correct
17	Correct	1480 ms	6716 KB	Output is correct
18	Correct	99 ms	2516 KB	Output is correct
19	Correct	2258 ms	6960 KB	Output is correct
20	Correct	2264 ms	6964 KB	Output is correct