Submission #1189977

#	Time	Username	Problem	Language	Result	Execution time	Memory
1189977		andrei_n	Awesome Arrowland Adventure (eJOI19_adventure)	C++20	100 / 100	41 ms	5560 KiB

adventure

#include <bits/stdc++.h>
#define newx x+dx[i]
#define newy y+dy[i]

using namespace std;

struct Coord
{
    int x,y;
};

struct comp
{
    bool operator()(const pair<int,Coord> &a, const pair<int,Coord> &b) const
    {
        return a.first > b.first;
    }
};

enum {X, N, E, S, W};
const int INF = 9999999;
const int dx[] = {0,-1,0,1,0};
const int dy[] = {0,0,1,0,-1};
int dir[128];
int v[505][505];
int cost[505][505];
priority_queue<pair<int,Coord>, vector<pair<int,Coord>>, comp> pq;

inline int dist(int a, int b)
{
    if(a == X) return INF;
    return (a <= b ? b-a : b-a+4);
}

signed main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int n,m; cin>>n>>m;
    char ch;
    dir['N'] = N;
    dir['E'] = E;
    dir['S'] = S;
    dir['W'] = W;
    dir['X'] = X;
    for(int i=1; i<=n; ++i)
        for(int j=1; j<=m; ++j)
        {
            cin>>ch;
            v[i][j] = dir[ch];
            cost[i][j] = INF;
        }
    cost[1][1] = 0;
    pq.emplace(0, Coord({1,1}));
    while(!pq.empty())
    {
        int c = pq.top().first;
        int x = pq.top().second.x;
        int y = pq.top().second.y;
        pq.pop();
        if(cost[x][y] != c || v[x][y] == X) continue;
        for(int i=1; i<=4; ++i)
        {
            if(cost[newx][newy] > c + dist(v[x][y], i))
            {
                cost[newx][newy] = c + dist(v[x][y], i);
                pq.emplace(cost[newx][newy], Coord({newx, newy}));
            }
        }
    }
    cout<<(cost[n][m] == INF ? -1 : cost[n][m]);
    return 0;
}

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