Submission #969814

#	Time	Username	Problem	Language	Result	Execution time	Memory
969814		steveonalex	Robots (APIO13_robots)	C++17	0 / 100	4 ms	15964 KiB

robots

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef unsigned long long ull;
 
#define ALL(v) (v).begin(), (v).end()
#define MASK(i) (1LL << (i))
#define GETBIT(mask, i) (((mask) >> (i)) & 1)
 
// mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng(1);
ll rngesus(ll l, ll r){return ((ull) rng()) % (r - l + 1) + l;}
 
ll max(ll a, ll b){return (a > b) ? a : b;}
ll min(ll a, ll b){return (a < b) ? a : b;}
 
ll LASTBIT(ll mask){return mask & (-mask);}
ll pop_cnt(ll mask){return __builtin_popcountll(mask);}
ll ctz(ll mask){return __builtin_ctzll(mask);}
ll clz(ll mask){return __builtin_clzll(mask);}
ll logOf(ll mask){return 63 - clz(mask);}
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if (a > b){a = b; return true;}
        return false;
    }
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if (a < b){a = b; return true;}
        return false;
    }
template <class T>
    void printArr(T& a, string separator = " ", string finish = "\n", ostream& out = cout){
        for(auto i: a) out << i << separator;
        out << finish;
    }
template <class T>
    void remove_dup(vector<T> &a){
        sort(ALL(a));
        a.resize(unique(ALL(a)) - a.begin());
    }

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

const int N = 501, K = 2, INF = 1e9 + 69;

enum GridObj{none=0, obstacle=1, anti_clockwise=2, clockwise=3};

int n, w, h;
int dp[K][K][N][N];
int dis[N][N][4];
bool visited[N][N][4];


GridObj grid[N][N];
pair<int, int> pos[9];

vector<array<int, 3>> q[N * N];

void dijkstra(int l, int r){

    memset(dis, 63, sizeof dis);
    int cnt = 0;
    if (l == r){
        for(int i = 1; i<=w; ++i) for(int j = 1;j <=h; ++j) if (dp[l][r][i][j] < INF) {
            for(int x = 0; x < 4; ++x){
                dis[i][j][x] = dp[l][r][i][j];
                q[dp[l][r][i][j]].push_back({{i, j, x}});
                cnt++;
            }
        }
    }

    for(int distance = 0; cnt > 0; ++distance){
        while(q[distance].size()){
            array<int, 3> u = q[distance].back(); q[distance].pop_back();
            cnt--;

            if (visited[u[0]][u[1]][u[2]]) continue;
            visited[u[0]][u[1]][u[2]] = true;
            
            array<int, 3> v = {{u[0] + dx[u[2]], u[1]+ dy[u[2]], u[2]}};
            if (grid[v[0]][v[1]] == anti_clockwise) v[2] = (v[2] + 1) % 4;
            else if (grid[v[0]][v[1]] == clockwise) v[2] = (v[2] + 3) % 4;

            if (grid[v[0]][v[1]] == obstacle){
                minimize(dp[l][r][v[0]][v[1]], distance + 1);
                for(int x = 0; x < 4; ++x){
                    array<int, 3> v = {{u[0] + dx[x], u[1] + dy[x], x}};
                    if (grid[v[0]][v[1]] != obstacle && minimize(dis[v[0]][v[1]][v[2]], distance + 1)) {
                        q[distance + 1].push_back(v);
                        cnt++;
                    }
                }
            }
            else {
                if (minimize(dis[v[0]][v[1]][v[2]], distance)) {
                    q[distance].push_back(v);
                    cnt++;
                }
            }
        }
    }
}

int main(void){
    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    cin >> n >> w >> h;
    swap(w, h);
    if (n == 1){
        cout << 0 << "\n";
        return 0;
    }
    if (n > 2) return -1;
    for(int i = 0; i<=w+1; ++i) 
    for(int j = 0; j<=h+1; ++j) grid[i][j] = obstacle;
    for(int i = 0; i<w; ++i){
        string s; cin >> s;
        for(int j = 0; j<h; ++j){
            if (s[j] == '.') grid[i+1][j+1]=none;
            else if (s[j] == 'x') grid[i+1][j+1] = obstacle;
            else if (s[j] == 'A') grid[i+1][j+1] = anti_clockwise;
            else if (s[j] == 'C') grid[i+1][j+1] = clockwise;
            else pos[s[j] - '0' - 1] = {i + 1, j + 1};
        }
    }

    memset(dp, 63, sizeof dp);

    for(int i = 0; i<n; ++i){
        dp[i][i][pos[i].first][pos[i].second] = 0;
    }

    for(int i = 0; i<n; ++i){
        dijkstra(i, i);
    }
    
    int ans = INF;
    for(int i = 1; i<=w; ++i) for(int j = 1; j<=w; ++j) 
        minimize(ans, dp[0][0][i][j] + dp[1][1][i][j]);

    if (ans == INF) ans = -1;
    cout << ans << "\n";


    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 0 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 40