Submission #1019327

#	Time	Username	Problem	Language	Result	Execution time	Memory
1019327		MrPavlito	Awesome Arrowland Adventure (eJOI19_adventure)	C++17	100 / 100	73 ms	28240 KiB

adventure

#include <bits/stdc++.h>
#define int long long
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define sc second
#define endl "\n"
#define pii pair<int,int>

using namespace std;

const int MAXN = 500*500+5;
const int mod7 = 1e9+7;
const long long inf = 1e18;


vector<vector<pii>> graf(MAXN);
int n,m;

int calc(char a)
{
    if(a == 'E')return 1;
    if(a == 'S')return 2;
    if(a == 'W')return 3;
    if(a == 'N')return 4;
    return INT_MAX;
}

int f(char a, char b)
{
    int t =(calc(b) - calc(a));
    if(t<0)return 4+t;
    else return t;
}

set<pii> que;
vector<int> dist(MAXN, inf);


void dikstra(int nod)
{
    dist[nod] = 0;
    que.insert(mp(0, nod));
    while(!que.empty())
    {
        auto it = que.begin();
        int u = it -> second;
        que.erase(it);
        for(auto x: graf[u])
        {
            int v = x.fi; int w = x.sc;
            if(dist[v] > dist[u]+w)
            {
                que.erase({dist[v], v});
                dist[v] = dist[u] + w;
                que.insert({dist[v], v});
            }
        }
    }

}

signed main()
{
    ios_base::sync_with_stdio(false),cin.tie(0), cout.tie(0);
    int tt=1;
    //cin >> tt;
    while(tt--)
    {
        cin >> n >> m;
        vector<vector<char>> mat(n, vector<char>(m));
        for(int i=0; i<n; i++)
        {
            string s;cin >> s;
            for(int j=0; j<m;j++)
            {
                mat[i][j] = s[j];
                if(calc(s[j]) == INT_MAX)continue;
                if(i!=n-1)graf[i*m+j].pb(mp( (i+1)*m+j,f(mat[i][j], 'S')));
                if(i!=0)graf[i*m+j].pb(mp((i-1)*m+j,f(mat[i][j], 'N')));
                if(j!=0)graf[i*m+j].pb(mp(i*m+j-1,f(mat[i][j], 'W')));
                if(j!=m-1)graf[i*m+j].pb(mp(i*m+j+1,f(mat[i][j], 'E')));
            }
        }
        for(int i=0; i<n; i++)
        dikstra(0);
        if(dist[n*m-1] == inf)cout << -1 << endl;
        else cout << dist[n*m-1] << endl;

    }
}

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