Submission #53851

#	Time	Username	Problem	Language	Result	Execution time	Memory
53851		ainta	Sandwich (JOI16_sandwich)	C++17	100 / 100	6194 ms	11968 KiB

sandwich

#include<cstdio>
#include<algorithm>
#include<vector>
using namespace std;
int Q[3 << 17], Deg[3 << 17], Res[3 << 17], ord[3 << 17], cnt, vis[3 << 17];
char p[1 << 9][1 << 9];
int F[3 << 17][2], CF[3 << 17];
int n, m;
int Num(int x, int y, int ck) {
	if (x<1 || x>n || y<1 || y>m)return 0;
	int cc = 0;
	if (p[x][y] == 'N') {
		if (ck == 0 || ck == 3)cc = 1;
		else cc = 2;
	}
	else {
		if (ck == 0 || ck == 2)cc = 1;
		else cc = 2;
	}
	return ((x - 1)*m + (y - 1)) * 2 + cc;
}
void Add_Edge(int a, int b) {
	if (!a || !b)return;
	Deg[a]++;
	F[b][CF[b]++] = a;
}
int main() {
	int i, j;
	//freopen("input.txt", "r", stdin);
	scanf("%d%d", &n, &m);
	for (i = 1; i <= n; i++) {
		scanf("%s", p[i] + 1);
	}
	for (i = 1; i <= n; i++) {
		for (j = 1; j <= m; j++) {
			Add_Edge(Num(i, j, 0), Num(i - 1, j, 0));
			Add_Edge(Num(i, j, 1), Num(i + 1, j, 1));
			Add_Edge(Num(i, j, 2), Num(i, j - 1, 2));
			Add_Edge(Num(i, j, 3), Num(i, j + 1, 3));
		}
	}
	int head = 0, tail = 0;
	for (i = 1; i <= n*m * 2; i++) {
		if (!Deg[i])Q[++tail] = i;
	}
	while (head < tail) {
		int x = Q[++head];
		for (int ii = 0; ii < CF[x];ii++) {
			int t = F[x][ii];
			Deg[t]--;
			if (!Deg[t])Q[++tail] = t;
		}
	}
	for (i = 1; i <= tail; i++)ord[++cnt] = Q[i];
	int cur = 0;
	for (i = 1; i <= n; i++) {
		cur++;
		for (j = 1; j <= m; j++) {
			int bs = Num(i, j, 3);
			int head = 0, tail = 0;
			if (vis[bs] != cur && !Deg[bs]) {
				vis[bs] = cur, Res[bs] += m - j + 1;
				Q[++tail] = bs;
			}
			while (head < tail) {
				int x = Q[++head];
				for (int ii = 0; ii < CF[x]; ii++) {
					int t = F[x][ii];
					if (vis[t] != cur && !Deg[t]) {
						vis[t] = cur, Res[t] += m - j + 1;
						Q[++tail] = t;
					}
				}
			}
		}
		cur++;
		for (j = m; j >= 1; j--) {
			int bs = Num(i, j, 2);
			int head = 0, tail = 0;
			if (vis[bs] != cur && !Deg[bs]) {
				vis[bs] = cur, Res[bs] += j;
				Q[++tail] = bs;
			}
			while (head < tail) {
				int x = Q[++head];
				for (int ii = 0; ii < CF[x]; ii++) {
					int t = F[x][ii];
					if (vis[t] != cur && !Deg[t]) {
						vis[t] = cur, Res[t] += j;
						Q[++tail] = t;
					}
				}
			}
		}
	}
	for (i = 1; i <= n; i++) {
		for (j = 1; j <= m; j++) {
			int bs = ((i - 1)*m + j - 1) * 2, res = 1e9;
			if (!Deg[bs + 1])res = min(res, Res[bs + 1]);
			if (!Deg[bs + 2])res = min(res, Res[bs + 2]);
			if (res > 8e8)res = -1;
			else res *= 2;
			printf("%d ", res);
		}
		printf("\n");
	}
}

Compilation message (stderr)

sandwich.cpp: In function 'int main()':
sandwich.cpp:30:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d", &n, &m);
  ~~~~~^~~~~~~~~~~~~~~~
sandwich.cpp:32:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%s", p[i] + 1);
   ~~~~~^~~~~~~~~~~~~~~~

• Subtask 1: 35 / 35
• Subtask 2: 65 / 65