Submission #1166812

#	Time	Username	Problem	Language	Result	Execution time	Memory
1166812		Kerim	Robots (APIO13_robots)	C++20	100 / 100	1345 ms	117476 KiB

robots

#include "bits/stdc++.h"

using namespace std;

#define ff first
#define ss second
#define ll long long

const int N = 505;

char a[N][N];

int mp[N][N], n, w, h, ind[10], nd, dpfn[10][10][N*N];

pair <int, int> dp[N][N][4];

vector <vector <int>> v;

pair <int, int> f(int i, int j, int x) {
    if(dp[i][j][x] != pair <int, int> {0, 0}) return dp[i][j][x];
    int x1 = (x % 2 ? 0 : (!x ? -1 : 1)), y1 = (!(x % 2) ? 0 : (x == 1 ? 1 : -1));
    if(a[i + x1][j + y1] != 'x' and i + x1 <= h and i + x1 > 0 and j + y1 <= w and j + y1 > 0) {
        int xx = x, i1 = i, j1 = j;
        i += x1, j += y1;
        if(a[i][j] == 'C') {
            x++;
            if(x == 4) x = 0;
        }
        if(a[i][j] == 'A') {
            x--;
            if(x == -1) x = 3;
        }
        return dp[i1][j1][xx] = f(i, j, x);
    }
    return dp[i][j][x] = pair <int, int> {i, j};
}

void compute(int a, int b, vector <pair <int, int>>&q2){
	queue<pair<int,int> > q;
    while(!q.empty() or !q2.empty()) {

    	bool ok = 0;
        if (q2.empty())
            ok = 1;
        else if (!q.empty() && q.front().first < q2.back().first)
            ok = 1;
        auto [cost, x] = ok ? q.front() : q2.back();
        if (ok)
            q.pop();
        else
            q2.pop_back();

        for(auto i : v[x]) {
            if(dpfn[a][b][i] > cost+1) {
                dpfn[a][b][i] = cost+1;
                q.push({dpfn[a][b][i], i});
            }
        }
    }

}
void fn(int a, int b) {
    vector <pair <int, int>> q;
    for(int k = a; k < b; k++)
        for(int node = 1; node <= nd; node++)
            dpfn[a][b][node] = min(dpfn[a][b][node], dpfn[a][k][node] + dpfn[k+1][b][node]);
    for(int k = a; k < b; k++)
        for(int node = 1; node <= nd; node++)
            if(dpfn[a][b][node] != 1e9)
                q.push_back({dpfn[a][b][node], node});

    sort(q.begin(), q.end(), greater<pair<int,int>>());
    compute(a, b, q);
}

signed main() {
    ios_base::sync_with_stdio(false); cin.tie(nullptr);

    cin >> n >> w >> h;

    for(int i = 1; i <= h; i++) {
        for(int j = 1; j <= w; j++) {
            cin >> a[i][j];
            mp[i][j] = ++nd;
            if(a[i][j] >= '1' and a[i][j] <= '9') ind[a[i][j] - '0'] = nd;
        }
    }

    for(int i = 1; i <= n; i++) {
        for(int i1 = 1; i1 <= n; i1++) {
            for(int i2 = 1; i2 <= nd; i2++) {
                dpfn[i][i1][i2] = 1e9;
            }
        }
    }

    v.resize(nd+1);
    for(int i = 1; i <= h; i++) {
        for(int j = 1; j <= w; j++) {
            for(int k = 0; k < 4; k++) {
                pair <int, int> ind = f(i, j, k);
                if(ind != pair <int, int> {i, j}) v[mp[i][j]].push_back(mp[ind.ff][ind.ss]);
            }
        }
    }

    vector <pair <int, int>> q;
    for(int i = 1; i <= n; i++) {
        dpfn[i][i][ind[i]] = 0;
        q.push_back({0, ind[i]});
        compute(i, i, q);
    }

    for(int i = 0; i < n; i++)
        for(int a = 1; a + i <= n; a++)
            fn(a, a + i);

    int ans = 1e9;

    for(int i = 1; i <= nd; i++) 
        ans = min(ans, dpfn[1][n][i]);

    cout << (ans == 1e9 ? -1 : ans) << "\n";

    return 0;
}

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