Submission #1197631

#	Time	Username	Problem	Language	Result	Execution time	Memory
1197631		TahirAliyev	Tracks in the Snow (BOI13_tracks)	C++20	100 / 100	655 ms	318192 KiB

tracks

#include <bits/stdc++.h>

// #pragma GCC optimize("Ofast,no-stack-protector,unroll-loops")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
// #define int long long
#define ll long long
#define pii pair<int, int>
#define all(v) v.begin(), v.end()
using namespace std;
const int oo = 1e9 + 9;
const int MAX = 4000 + 5, LOGMAX = 20, B = 441, MOD = 998244353;

int n, m;
int vis[MAX][MAX];
vector<char> ch = {'R', 'F'};
vector<pii> dir = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};
string arr[MAX];
 
void solve(){
    cin >> n >> m;
    bool r = 0, f = 0;
    for(int i = 1; i <= n; i++){
        cin >> arr[i];
        arr[i] = '%' + arr[i];
    }
    if(arr[1][1] == '.'){
        cout << "0\n";
        return;
    }
    int ans = 0;
    deque<pii> q;
    q.push_back({1, 1});
    char pr = '$';
    while(q.size()){
        pii a = q.front();
        q.pop_front();
        if(vis[a.first][a.second]) continue;
        vis[a.first][a.second] = 1;
        if(arr[a.first][a.second] != pr) ans++;
        pr = arr[a.first][a.second];
        for(auto d : dir){
            int nx = a.first + d.first;
            int ny = a.second + d.second;
            if(!(1 <= nx && nx <= n && 1 <= ny && ny <= m) || (arr[nx][ny] == '.')) continue;
            if(arr[nx][ny] == pr) q.push_front({nx, ny});
            else q.push_back({nx, ny});
        }
    }
    cout << ans << '\n';
}   

signed main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t = 1;
    // cin >> t;
    while(t--) solve();
}

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