제출 #817808

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
817808		Boomyday	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	770 ms	162588 KiB

tracks

//
// Created by adavy on 1/31/2023.
//
// My Header
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;
using db = double;
using str = string; // yay python!

using ii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;

using vi = vector<int>;
using vb = vector<bool>;
using vl = vector<ll>;
using vd = vector<db>;
using vs = vector<str>;
using vii = vector<ii>;
using vpl = vector<pl>;
using vpd = vector<pd>;

#define tcT template<class T
#define tcTU tcT, class U

tcT> using V = vector<T>;
tcT, size_t SZ> using AR = array<T,SZ>;
tcT> using PR = pair<T,T>;

// pairs
#define mp make_pair
#define f first
#define s second



#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define trav(a,x) for (auto& a: x)

#define len(x) int((x).size())
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define sor(x) sort(all(x))
#define rsz resize
#define ins insert
#define ft front()
#define bk back()
#define pb push_back
#define eb emplace_back
#define pf push_front

const int MOD = 1e9+7; // 998244353;
const int MX = 2e5+5;
const ll INF = 1e18; // not too close to LLONG_MAX
const ld PI = acos((ld)-1);
const int dx[4] = {1,0,-1,0}, dy[4] = {0,1,0,-1}; // for every grid problem!!


int main(){
    // 0-1 bfs

    int H, W; cin >> H >> W;


    vector<vi> grid;

    F0R(i, H){
        string row; cin >> row;
        vector<int> x;
        trav(c, row){
            if (c=='R') x.pb(1);
            else if (c=='F') x.pb(-1);
            else x.pb(0);
        }
        grid.pb(x);
    }

    vector<vector<bool>> vis(H,vb(W,0));
    vector<vector<int>> dist(H,vi(W));

    deque<ii> q;
    q.push_back({0,0});
    dist[0][0] = 1; // H, W
    vis[0][0] = 1;
    int ans = 1;

    while(q.size()){
        auto [x, y] = q.front(); q.pop_front();

        ans = max(ans, dist[x][y]);
        F0R(d, 4){
            int nx = x+dx[d], ny = y+dy[d];
            if(!(0<=nx && nx<H && 0<=ny && ny<W)) continue;
            if (vis[nx][ny]) continue;
            if (grid[nx][ny]==0) continue;
            vis[nx][ny] = 1;
            if (grid[nx][ny]==grid[x][y]){
                q.push_front({nx,ny});
                dist[nx][ny] = dist[x][y];
                
            }
            else if (grid[nx][ny]==-grid[x][y]){
                q.push_back({nx,ny});
                dist[nx][ny] = dist[x][y]+1;
            }
        }
    }
    cout << ans << endl;


}

• Subtask 1: 30 / 30
• Subtask 2: 70 / 70