Submission #36713

#	Time	Username	Problem	Language	Result	Execution time	Memory
36713		RockyB	Sailing Race (CEOI12_race)	C++14	40 / 100	493 ms	6564 KiB

race

/// In The Name Of God

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,sse3,sse4,popcnt,abm,mmx")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)500 + 7, inf = (int)1e9 + 7, mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;
const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1}, dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n, k;
vector <int> g[N];
bool ok[N][N];

int dp[N][N][2][2];
int calc(int l, int r, bool type, bool f) {
	if (~dp[l][r][type][f]) return dp[l][r][type][f];
	int v = !f ? l : r;
	int res = 0;
	for (auto to : g[v]) {
		if (to == l || to == r) continue;
		if (type) {
			if (l < to && to < r) {
				res = max(res, max(calc(l, to, type, 1), calc(to, r, type, 0)) + 1);
			}
		}
		else {	
			if (!(l < to && to < r)) {
				if (to > r) {
					res = max(res, max(calc(l, to, 0, 1), calc(r, to, 1, 1)) + 1);
				}
				else {
					res = max(res, max(calc(to, l, 1, 0), calc(to, r, 0, 0)) + 1);
				}
			}
		}
	}
	return dp[l][r][type][f] = res;
}
int main() {
	#ifdef IOI2018
		freopen ("in.txt", "r", stdin);
	#endif
	srand(time(0));
	scanf ("%d%d", &n, &k);
	for (int i = 1; i <= n; i++) {
		int to;
		while (scanf ("%d", &to) && to) {
			ok[i][to] = 1;
			g[i].pb(to);
		}
	}
	if (n == 1) {
		printf ("0\n1");
		ioi
	}
	if (!k || k) {
		int mx = 0, opt = 1;
		memset(dp, -1, sizeof(dp));
		vector <int> can;
		for (int i = 1; i <= n; i++) {
			for (auto to : g[i]) {
				int now = max(calc(min(i, to), max(i, to), 0, i < to), calc(min(i, to), max(i, to), 1, i < to)) + 1;
				if (now > mx) {
					mx = now;
					opt = i;
				}
			}
		}
		for (int i = 1; i <= n; i++) {
			for (auto to : g[i]) {
				int now = max(calc(min(i, to), max(i, to), 0, i < to), calc(min(i, to), max(i, to), 1, i < to)) + 1;
				if (now == mx) {
					can.pb(i);
				}
			}
		}
		if (!k) printf ("%d\n%d", mx, opt);
		else {
			random_shuffle(all(can));
			printf ("%d\n%d", mx + 1, can[0]);
		}
		ioi
	}
	else assert(0);
	ioi
}

Compilation message (stderr)

race.cpp: In function 'int main()':
race.cpp:68:24: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf ("%d%d", &n, &k);
                        ^

• Subtask 1: 40 / 100