Submission #828759

#	Time	Username	Problem	Language	Result	Execution time	Memory
828759		ZeroCool	Awesome Arrowland Adventure (eJOI19_adventure)	C++14	100 / 100	43 ms	7308 KiB

adventure

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define mp make_pair
#define pb push_back

using ll = long long;
using ld = long double;


void solve(int T);
void pre();

const int mxn = 1e5 + 5;
const int SQRT = 500;
const int LOG = 20;
const int inf = 1e18;
const int mod = 1e9 + 7;
const ld eps = 1e-9;

int32_t main(){
	pre();
	int tt = 1;
	//cin>>tt;
	for(int i = 1;i<=tt;i++)solve(i);
    return 0;
}



void pre(){
	#ifdef ONLINE_JUDGE
    ios::sync_with_stdio(false);
    cin.tie(0);
	#endif
	
}

int dir[4][2] = {
	{0,-1}, //N
	{1,0}, // E
	{0,1},//  S
	{-1,0}//  W
};

int val(char c){
	if(c == 'N')return 0;
	if(c == 'E')return 1;
	if(c == 'S')return 2;
	if(c == 'W')return 3;
	return -1;
}

struct Node{
	int x;
	int y;
	int cost;
};

bool operator<(Node a,Node b){
	return a.cost > b.cost;
}

int n,m;

bool in(int x,int y){
	return x >= 0 && y >= 0 && x<n && y < m;
}

void solve(int T){
	cin>>n>>m;
	char A[n][m];
	bool vis[n][m];

	for(int i = 0;i<n;i++){
		for(int j = 0;j<m;j++){
			char c;
			cin>>c;
			vis[i][j] = false;
			A[i][j] = c;
		}
	}

	priority_queue<Node> pq;
	pq.push({0,0,0});

	while(pq.size()){
		Node t = pq.top();
		pq.pop();
		int x = t.x;
		int y = t.y;
		int cost = t.cost;
		if(vis[x][y])continue;
		vis[x][y] = true;

		int arrow = val(A[x][y]);
		
		if(x == n-1 && y == m-1){
			cout<<cost<<endl;
			return;
		}
		if(arrow == -1)continue;
		for(int i = 0;i<4;i++){
			int d = (i + arrow)% 4;

			int nx = x + dir[d][1];
			int ny = y + dir[d][0];

			if(!in(nx,ny))continue;
			if(!vis[nx][ny])pq.push({nx,ny,cost + i});
		}
	}
	cout<<-1<<endl;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 12 / 12
• Subtask 4: 16 / 16
• Subtask 5: 50 / 50