Submission #976844

#	Time	Username	Problem	Language	Result	Execution time	Memory
976844		vjudge1	Awesome Arrowland Adventure (eJOI19_adventure)	C++17	100 / 100	110 ms	10436 KiB

adventure

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

#define ll long long
#define pb push_back
#define pll pair<ll,ll>

const ll MOD=1e9+7;
const ll INF= 1e9;

#define ll int
//KALAU TAKUT RTE

bool cmp (pair<ll,ll> x, pair<ll,ll>y){
	return x.second < y.second;
}

ll expo(ll x, ll y){
	if (y==0) return 1;
	ll ans = expo((x*x)%MOD, y/2);
	if (x%2) return (ans * x)%MOD;
	return ans%MOD;
}

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

char grid[505][505];
ll dis[505][505][5];

typedef tuple<ll,ll,ll,ll> state;
priority_queue<state, vector<state>, greater<state>> pq;


ll arah(ll x, ll y){
	if (grid[x][y] == 'N') return 0;
	if (grid[x][y] == 'E') return 1;
	if (grid[x][y] == 'S') return 2;
	if (grid[x][y] == 'W') return 3;
	return 4;
}


signed main(){
	ios_base::sync_with_stdio(0);cin.tie(0); cout.tie(0);
	ll n, m; cin>>n>>m;
	for (int i=1; i<=n;i++){
		for (int j=1; j<=m;j++){
			cin>>grid[i][j];
			for (int k=0; k<5;k++) dis[i][j][k]= INF;
		}
	}
	
	dis[1][1][arah(1,1)] = 0;
	pq.push({0,1,1,arah(1,1)});	
	
	while(!pq.empty()){
		auto [cost,y,x,d] = pq.top(); pq.pop();
		// cout<< cost<<" "<<y<<" "<<x<<" "<<d<<endl;
		if (d==4) continue;
		
		int nx = x+dx[d], ny=y+dy[d];
		if (nx > 0 && nx<=m && ny>0 && ny<=n){
			int nd = arah(ny,nx);
			if (dis[ny][nx][nd]	> cost){
				dis[ny][nx][nd] = cost;
				pq.push({cost, ny,nx,nd});
			}
		}
		
		int nd  = (d+1)%4;
		if (dis[y][x][nd] > cost+1){
			dis[y][x][nd]=cost+1;
			pq.push({cost+1, y, x, nd});
		}
		
	}
	if (dis[n][m][4] == INF) cout<<-1<<endl;
	else cout<<dis[n][m][4]<<endl;
	
}

Compilation message (stderr)

adventure.cpp:11: warning: "ll" redefined
   11 | #define ll int
      | 
adventure.cpp:4: note: this is the location of the previous definition
    4 | #define ll long long
      |

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