Submission #148111

#	Time	Username	Problem	Language	Result	Execution time	Memory
148111		WhipppedCream	Nautilus (BOI19_nautilus)	C++17	100 / 100	297 ms	1400 KiB

nautilus

#include <bits/stdc++.h>
#pragma GCC optimize ("O3")
#pragma GCC target ("sse4")
using namespace std;
#define X first
#define Y second
#define pb push_back
typedef pair<int, int> ii;
typedef long long ll;

const int maxn = 505;
const int maxs = 50005;
const int sz = 500*500;
int n, m, k;
char arr[maxn][maxn];
char dir[maxs];

int main()
{	
	scanf("%d %d %d", &n, &m, &k);
	for(int i = 0; i< n; i++) scanf("%s", arr[i]);
	bitset<sz> mask;
	bitset<sz> mright, mleft; 
	mright.set(); mleft.set();
	for(int i = 0; i< n; i++)
	{
		for(int j = 0; j< m; j++)
		{
			if(arr[i][j] == '#') mask[i*m+j] = 0;
			else mask[i*m+j] = 1;
			if(j == 0) mleft[i*m+j] = 0;
			if(j == m-1) mright[i*m+j] = 0;
		}
	}
	bitset<sz> dp;
	for(int i = 0; i< n; i++)
	{
		for(int j = 0; j< m; j++)
		{
			dp[i*m+j] = 1;
		}
	}
	dp &= mask;
	// printf("%d\n", dp.count());
	scanf("%s", dir);
	for(int i = 0; i< k; i++)
	{
		if(dir[i] == 'N')
		{
			dp = dp>>m;
		}
		else if(dir[i] == 'S')
		{
			dp = dp<<m;
		}
		else if(dir[i] == 'E')
		{
			dp = (dp<<1)&mleft;
		}
		else if(dir[i] == 'W') 
		{
			dp = (dp>>1)&mright;
		}
		else 
		{
			dp = (dp>>m)|(dp<<m)|((dp<<1)&mleft)|((dp>>1)&mright);
		}
		dp &= mask;
	}
	printf("%d\n", (int) dp.count());
}

Compilation message (stderr)

nautilus.cpp: In function 'int main()':
nautilus.cpp:20:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d %d", &n, &m, &k);
  ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
nautilus.cpp:21:33: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  for(int i = 0; i< n; i++) scanf("%s", arr[i]);
                            ~~~~~^~~~~~~~~~~~~~
nautilus.cpp:45:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%s", dir);
  ~~~~~^~~~~~~~~~~

• Subtask 1: 29 / 29
• Subtask 2: 37 / 37
• Subtask 3: 34 / 34