Submission #891814

#	Time	Username	Problem	Language	Result	Execution time	Memory
891814		seriouslyFlawed	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	1100 ms	119196 KiB

tracks

#include <bits/stdc++.h>

using namespace std;

// Shortcuts for common operations
#define pb push_back
#define ppb pop_back
#define f first
#define s second
#define all(x) (x).begin(), (x).end()
#define ll long long
#define endl "\n"

// Type definitions for convenience
typedef vector<int> vi;
typedef vector<bool> vb;
typedef pair<int, int> pii;
typedef vector<vi> vvi;
typedef vector<pii> vii;
typedef unordered_set<int> usi;
typedef unordered_map<int, int> umii;

// Debugging macros
#define debug(x) cerr << #x << " = " << (x) << '\n'
#define debug_vector(v) _debug_vector(#v, v)
template<typename T>
void _debug_vector(const string& name, const vector<T>& a) {
    cerr << name << " = [ ";
    for(const auto &x : a) cerr << x << ' ';
    cerr << "]\n";
}

// I/O redirection for local testing
#define iofile(io) \
        freopen((io + ".in").c_str(), "r", stdin); \
        freopen((io + ".out").c_str(), "w", stdout);

// delta for floodfill
vi dx = {0, 1, 0, -1};
vi dy = {1, 0, -1, 0};

// extended deltas for floodfill
vi edx = {0, 1, 0, -1, 1, 1, -1, -1};
vi edy = {1, 0, -1, 0, 1, -1, 1, -1};

// Common outputs
void yes() { cout << "YES" << '\n'; }
void no() { cout << "NO" << '\n'; }

// cin.tie(0)->sync_with_stdio(0);

void fx() {
    // Functionality for fx
    int n, m;
    cin >> n >> m;

    vector<string>tab(n);
    for(auto &i: tab) cin >> i;

    vvi lvl(n, vi(m, 0));
    lvl[0][0] = 1;

    queue<pii>q;
    q.push({0, 0});

    queue<pii>que;
    int res = 1;

    while(!q.empty()){
        while(!q.empty()){
            auto curr = q.front(); q.pop();

            for(int i = 0; i < 4; i++){
                pii next = {curr.f+dx[i], curr.s+dy[i]};

                if(next.f >= 0 and next.f <= n-1 and next.s >= 0 and next.s <= m-1){
                    if(tab[next.f][next.s] == '.' or lvl[next.f][next.s] != 0) continue;
                    

                    if(tab[next.f][next.s] == tab[curr.f][curr.s]){ q.push(next); lvl[next.f][next.s] = res; }
                    else{ que.push(next); lvl[next.f][next.s] = res+1; }
                }
            }
        }

        if(q.empty()){
            res++;
            swap(q, que);
        }
    }


    cout << (res-1) << endl;

}

int main() {
    // Uncomment the following lines for file I/O
    // iofile(string("hello"));
    
    // Uncomment the following lines for multiple test cases
    // int t; cin >> t;
    // while(t--) fx();
    
    // Single test case
    fx();
    
    return 0;
}

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