Submission #750235

#	Time	Username	Problem	Language	Result	Execution time	Memory
750235		MuntherCarrot	Awesome Arrowland Adventure (eJOI19_adventure)	C++14	0 / 100	4 ms	6484 KiB

adventure

#include <bits/stdc++.h>
using namespace std;
#define ll long long
// #define int long long
#define endl '\n'
#define all(x) x.begin(),x.end()
const ll MOD = 1e9 + 7, SZ = 1e5 + 10, INF = 1e18;
vector<vector<int>> vtx(SZ);
int cst[4][4] = {
    {0, 1, 2, 3}, //N
    {3, 0, 1, 2}, //E
    {2, 3, 0, 1}, //S
    {1, 2, 3, 0}  //W
//   N  E  S  W
};
int32_t main(){
    // ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int n, m;
    cin >> n >> m;
    char arr[n][m];
    for(auto &I : arr){
        for(char &i : I)
            cin >> i;
    }
    int nds[n][m];
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++)
            nds[i][j] = i * m + j;
    }
    int mtx[n*m][n*m];
    memset(mtx, -1, sizeof mtx);
    for(int i=0;i<n;i++){
        for(int j=0;j<m;j++){
            int y = nds[i][j];
            int d;
            if(arr[i][j] == 'X')
                d = -1;
            if(arr[i][j] == 'N')
                d = 0;
            if(arr[i][j] == 'E')
                d = 1;
            if(arr[i][j] == 'S')
                d = 2;
            if(arr[i][j] == 'W')
                d = 3;
            if(j > 0)
                mtx[y][nds[i][j - 1]] = (d == -1 ? -1 : cst[d][3]);
            if(i > 0)
                mtx[y][nds[i - 1][j]] = (d == -1 ? -1 : cst[d][0]);
            if(j + 1 < m)
                mtx[y][nds[i][j + 1]] = (d == -1 ? -1 : cst[d][1]);
            if(i + 1 < n)
                mtx[y][nds[i + 1][j]] = (d == -1 ? -1 : cst[d][2]);
        }
    }
    // for(int i=0;i<n * m;i++){
    //     for(int j=0;j<n * m;j++)
    //         if(mtx[i][j] != -1)cout << mtx[i][j] << ' ';
    //     cout << endl;
    // }
    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> q;
    q.push({0, 0});
    vector<int> ans(n * m, INT_MAX);
    bool vis[n * m] = {};
    while(!q.empty()){
        auto u = q.top();
        q.pop();
        if(vis[u.second])
            continue;
        // cout << u. first << ' ' << u.second << endl;
        vis[u.second] = 1;
        ans[u.second] = u.first;
        for(int i=0;i<n * m;i++){
            if(mtx[u.second][i] == -1)
                continue;
            // cout << i << ' '<< mtx[u.second][i] + u.first << endl;
            q.push({mtx[u.second][i] + u.first, i});
        }
    }
    // for(int i=0;i<m*n;i++)
    //     cout << ans[i] << ' ';
    cout << ans[n * m - 1];
    return 0;
}

Compilation message (stderr)

adventure.cpp: In function 'int32_t main()':
adventure.cpp:49:50: warning: 'd' may be used uninitialized in this function [-Wmaybe-uninitialized]
   49 |                 mtx[y][nds[i - 1][j]] = (d == -1 ? -1 : cst[d][0]);
      |                                         ~~~~~~~~~^~~~~~~~~~~~~~~~~

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