Submission #46085

#	Time	Username	Problem	Language	Result	Execution time	Memory
46085		RockyB	Robots (APIO13_robots)	C++14	30 / 100	1601 ms	163840 KiB

robots

/// In The Name Of God

#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb emplace_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 + 1;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n, m, h;
char a[N][N];

int dp[N][N][55];
int id[10][10];

pair <int, int> res[N][N][4];
bool add[N][N][4];
bool was[N][N][4];

struct node {
	int l, r, x, y;
	inline node() {}
	inline node(int l, int r, int x, int y) : l(l), r(r), x(x), y(y) {}
};

vector <node> q[N * N];

inline bool check(int x, int y) {
	return 0 <= x && x < n && 0 <= y && y < m && a[x][y] != 'x';
}
inline pair <int, int> go(int x, int y, int t) {
	if (a[x][y] == 'C') t = (t + 1) % 4;
	if (a[x][y] == 'A') t = (t + 3) % 4;
	if (was[x][y][t]) return res[x][y][t];
	was[x][y][t] = 1;
	if (check(x + dx[t], y + dy[t])) return res[x][y][t] = go(x + dx[t], y + dy[t], t);
	return res[x][y][t] = {x, y};
}

int main() {
	#ifdef IOI2018
		freopen ("in.txt", "r", stdin);
	#endif
	scanf ("%d%d%d", &h, &m, &n);

	int tmr = 0;
	for (int i = 0; i <= h; ++i) {
		for (int j = i; j <= h; ++j) {
			id[i][j] = tmr++;
		}
	}
	for (int i = 0; i < n; i++) {
		for (int j = 0; j < m; j++) {
			for (int c = 0; c < tmr; c++) dp[i][j][c] = inf;
			for (int c = 0; c < 4; c++) res[i][j][c].f = -1;
		}
	}

	for (int i = 0; i < n; ++i) {
		scanf ("%s", a[i]);
		for (int j = 0; j < m; ++j) {
			if (isdigit(a[i][j])) {
				int d = a[i][j] - '1';
				dp[i][j][id[d][d]] = 0;
				q[0].pb(node(d, d, i, j));
			}
		}
	}	
	for (int i = 0; i < n; ++i) {
		for (int j = 0; j < m; ++j) {
			if (check(i, j)) {
				for (int t = 0; t < 4; t++) {
					go(i, j, t);
					add[i][j][t] = mp(i, j) != res[i][j][t];
				}
			}
		}
	}
	int to = n * m;
	for (int cur = 0; cur <= to; ++cur) {
		for (auto v : q[cur]) {
			if (v.l == 0 && v.r == h - 1) cout << cur, ioi

			for (int t = 0; t < 4; ++t) {
				pair <int, int> to = res[v.x][v.y][t];
				if (to.f == -1) continue;

				//if (mp(v.x, v.y) == to) assert(0);

				int &up1 = dp[to.f][to.s][id[v.l][v.r]];
				if (up1 > cur + add[v.x][v.y][t]) {
					up1 = cur + add[v.x][v.y][t];
					q[up1].pb(node(v.l, v.r, to.f, to.s));
				}
				for (int i = v.r + 1; i < h; ++i) {
					if (dp[to.f][to.s][id[v.r + 1][i]] == inf) continue;
					int cost = cur + dp[to.f][to.s][id[v.r + 1][i]] + add[v.x][v.y][t];
					int &up2 = dp[to.f][to.s][id[v.l][i]];
					if (up2 > cost) {
						up2 = cost;
						q[up2].pb(node(v.l, i, to.f, to.s));
					}
				}
				for (int i = v.l - 1; i >= 0; --i) {
					if (dp[to.f][to.s][id[i][v.l - 1]] == inf) continue;
					int cost = cur + dp[to.f][to.s][id[i][v.l - 1]] + add[v.x][v.y][t];
					int &up3 = dp[to.f][to.s][id[i][v.r]];
					if (up3 > cost) {
						up3 = cost;
						q[up3].pb(node(i, v.r, to.f, to.s));
					}
				}
			}
		}
		if (sz(q[cur])) q[cur].clear();
	}
	cout << -1;
	ioi
}

Compilation message (stderr)

robots.cpp: In function 'int main()':
robots.cpp:72:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf ("%d%d%d", &h, &m, &n);
  ~~~~~~^~~~~~~~~~~~~~~~~~~~~~
robots.cpp:88:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf ("%s", a[i]);
   ~~~~~~^~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40