Submission #447632

#	Time	Username	Problem	Language	Result	Execution time	Memory
447632		idas	Awesome Arrowland Adventure (eJOI19_adventure)	C++11	38 / 100	2 ms	2380 KiB

adventure

#include <bits/stdc++.h>
#define FOR(i, begin, end) for(int i = (begin); i < (end); i++)
#define FAST_IO ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr)
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define SZ(x) ((int)((x).size()))
#define LE(vec) vec[vec.size()-1]
#define TSTS int t; cin >> t; while(t--)solve()

const int INF = 1e9;
const long long LINF = 1e18;
const long double PI = asin(1)*2;
const int MOD = 1e9+7;

using namespace std;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef map<int, int> mii;
typedef long long ll;
typedef long double ld;

void setIO()
{
    FAST_IO;
}

const int N=510;

int m, n, d[N][N], g[N][N];
bool v[N][N];
priority_queue<pair<int, pii>, vector<pair<int, pii>>, greater<pair<int, pii>>> q;

/*
-1-X
0-N
1-E
2-S
3-W
*/

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

pii re(int p, int x, int y)
{
    if(p==0) return MP(x, y-1);
    if(p==1) return MP(x+1, y);
    if(p==2) return MP(x, y+1);
    if(p==3) return MP(x-1, y);
}

int main()
{
    setIO();
    cin >> m >> n;
    FOR(i, 0, m)
    {
        FOR(j, 0, n)
        {
            char x;
            cin >> x;
            g[j][i]=c(x);
        }
    }

    FOR(i, 0, m) FOR(j, 0, n) d[j][i]=INF;

    v[n-1][m-1]=true;
    d[0][0]=0;
    q.push(MP(0, MP(0, 0)));
    while(!q.empty())
    {
        int k=q.top().F, x=q.top().S.F, y=q.top().S.S;
        if(!v[x][y])
        {
            v[x][y]=true;
            FOR(i, 0, 4)
            {
                int nx=re((g[x][y]+i)%4, x, y).F, ny=re((g[x][y]+i)%4, x, y).S;
                if(nx<0 || nx>=n || ny<0 || ny>=m || (g[nx][ny]==-1 && (nx!=n-1 || ny!=m-1))) continue;
                d[nx][ny]=min(d[nx][ny], k+i);
                q.push(MP(d[nx][ny], MP(nx, ny)));
            }
        }
        q.pop();
    }
    cout << (d[n-1][m-1]==INF?-1:d[n-1][m-1]);
}

Compilation message (stderr)

adventure.cpp: In function 'int c(char)':
adventure.cpp:50:1: warning: control reaches end of non-void function [-Wreturn-type]
   50 | }
      | ^
adventure.cpp: In function 'pii re(int, int, int)':
adventure.cpp:58:1: warning: control reaches end of non-void function [-Wreturn-type]
   58 | }
      | ^

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 12
• Subtask 4: 16 / 16
• Subtask 5: 0 / 50