oj.uz

답안 #680471

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
680471 2023-01-10T23:58:42 Z vjudge1 Sailing Race (CEOI12_race) C++17
100 / 100
 2276 ms 7088 KB 
#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 2 ms 2260 KB Output is correct
2 Correct 3 ms 4436 KB Output is correct
3 Correct 3 ms 4468 KB Output is correct
4 Correct 3 ms 4564 KB Output is correct
5 Correct 2 ms 2260 KB Output is correct
6 Correct 7 ms 4616 KB Output is correct
7 Correct 6 ms 2388 KB Output is correct
8 Correct 10 ms 4720 KB Output is correct
9 Correct 8 ms 2372 KB Output is correct
10 Correct 24 ms 2480 KB Output is correct
11 Correct 11 ms 2388 KB Output is correct
12 Correct 133 ms 5272 KB Output is correct
13 Correct 257 ms 5688 KB Output is correct
14 Correct 80 ms 2388 KB Output is correct
15 Correct 1524 ms 6652 KB Output is correct
16 Correct 1882 ms 6876 KB Output is correct
17 Correct 1450 ms 6836 KB Output is correct
18 Correct 104 ms 2516 KB Output is correct
19 Correct 2257 ms 6896 KB Output is correct
20 Correct 2276 ms 7088 KB Output is correct