Submission #261473

#	Time	Username	Problem	Language	Result	Execution time	Memory
261473		brcode	Robots (APIO13_robots)	C++14	60 / 100	644 ms	163844 KiB

robots

#include <iostream>
#include <bits/stdc++.h>
#pragma GCC target ("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#pragma GCC optimization ("Ofast")
using namespace std;
const int MAXN = 510;
char grid[MAXN][MAXN];
int dp[MAXN][MAXN][12][12];
vector<pair<int,int>> res[MAXN*MAXN + 2];
int n,h,w;
int dx[6] = {0,0,1,0,-1};
int dy[6] = {0,1,0,-1,0};
pair<int,int> visited[MAXN][MAXN][5];
pair<int,int> bot[20];
bool check(int i,int j){
    if(i<=0||j<=0||i>w||j>h||grid[i][j] == 'x'){
        return false;
    }
    return true;
}
pair<int,int> dfs(int i,int j,int dir){
    if(visited[i][j][dir]!=make_pair(0,0)){
        
        return visited[i][j][dir];
    }
    
    if(grid[i][j]!='x' && grid[i][j]!='C' && grid[i][j]!='A'){
        int nexti = i+dx[dir];
        int nextj = j+dy[dir];
        
        if(check(nexti,nextj)){
            
            return visited[i][j][dir] = dfs(nexti,nextj,dir);
        }else{
            
            return make_pair(i,j);
        }
        
    }
    if(grid[i][j]=='A'){
        int newdir = dir;
        newdir--;
        if(newdir == 0){
            newdir = 4;
        }
        int nexti = i+dx[newdir];
        int nextj = j+dy[newdir];
        if(check(nexti,nextj)){
            return visited[i][j][dir] = dfs(nexti,nextj,newdir);
        }else{
            return make_pair(i,j);
        }
        
    }
    
    if(grid[i][j]=='C'){
        int newdir = dir;
        newdir++;
        if(newdir == 5){
            newdir = 1;
        }
        int nexti = i+dx[newdir];
        int nextj = j+dy[newdir];
        if(check(nexti,nextj)){
            return visited[i][j][dir] = dfs(nexti,nextj,newdir);
        }else{
            return make_pair(i,j);
        }
    }
    return make_pair(0,0);
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin>>n>>w>>h;
    swap(w,h);
    int mx = h*w;
    for(int i=1;i<=w;i++){
        for(int j=1;j<=h;j++){
            char x;
            cin>>x;
            grid[i][j] = x;

            int y = x-'0';
            bot[y] = make_pair(i,j);
            
        }
    }
    for(int i=1;i<=w;i++){
        for(int j=1;j<=h;j++){
            for(int x=1;x<=n;x++){
                for(int y=1;y<=n;y++){
                    dp[i][j][x][y] = 1e9;
                }
            }
        }
    }
    for(int i=1;i<=n;i++){
        
                dp[bot[i].first][bot[i].second][i][i] = 0;
        //  cout<<i<<" "<<bot[i].first<<" "<<bot[i].second<<endl;
        
    }
    for(int i=1;i<=w;i++){
        for(int j=1;j<=h;j++){
            if(grid[i][j] == 'x'){
                continue;
            }
            if(visited[i][j][1]== make_pair(0,0)){
                dfs(i,j,1);
            }
            if(visited[i][j][2]== make_pair(0,0)){
                dfs(i,j,2);
            }
            if(visited[i][j][3]== make_pair(0,0)){
                dfs(i,j,3);
            }
            if(visited[i][j][4]== make_pair(0,0)){
                dfs(i,j,4);
            }
        }
    }
    //cout<<visited[5][5][1].first<<" "<<visited[5][5][1].second<<endl;
    for(int len=0;len<=n-1;len++){
        for(int x=1;x<=n;x++){
            int y = x+len;
            if(y>n){
                break;
            }
            for(int i=1;i<=w;i++){
                for(int j=1;j<=h;j++){
                    for(int z=x;z<y;z++){
                        if(i==1 && j==1 && x==1 && y==4 && z==2){
                            //cout<<dp[i][j][z+1][y]<<endl;
                        }
                        dp[i][j][x][y] = min(dp[i][j][x][y],dp[i][j][x][z]+dp[i][j][z+1][y]);
                    }
                }
            }
            
            for(int i=0;i<=w*h;i++){
                if(res[i].size()){
                    res[i].clear();
                }
            }
            for(int i=1;i<=w;i++){
                for(int j=1;j<=h;j++){
                    if(dp[i][j][x][y]!=1e9){
                        res[dp[i][j][x][y]].push_back(make_pair(i,j));
                        
                    }
                }
            }
            for(int i=0;i<=w*h;i++){
                for(auto tmp:res[i]){
                    int a = tmp.first;
                    int b = tmp.second;
                    for(int dir=1;dir<=4;dir++){
                        int nxti = visited[a][b][dir].first;
                        int nxtj = visited[a][b][dir].second;
                        if(nxti == a && nxtj == b){
                            continue;
                        }
                        if(nxti == 0 && nxtj == 0){
                            continue;
                        }
                        if(dp[nxti][nxtj][x][y]>i+1){
                            dp[nxti][nxtj][x][y] = i+1;
                            res[i+1].push_back(make_pair(nxti,nxtj));
                            
                        }
                    }
                }
            }
           
        }
    }
    //cout<<visited[1][7][3].first<<" "<<visited[1][7][3].second<<endl;
   // cout<<dp[1][7][3][4]<<endl;
    int ans = 1e9;
    for(int i=1;i<=w;i++){
        for(int j=1;j<=h;j++){
            ans = min(ans,dp[i][j][1][n]);
        }
    }
    if(ans == 1e9){
        ans = -1;
    }
    cout<<ans<<'\n';
}

Compilation message (stderr)

robots.cpp:4:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
 #pragma GCC optimization ("O3")
 
robots.cpp:5:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
 #pragma GCC optimization ("unroll-loops")
 
robots.cpp:6:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas]
 #pragma GCC optimization ("Ofast")
 
robots.cpp: In function 'int main()':
robots.cpp:79:9: warning: unused variable 'mx' [-Wunused-variable]
     int mx = h*w;
         ^~

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