제출 #410817

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
410817		stat0r1c	Tracks in the Snow (BOI13_tracks)	C++11	100 / 100	819 ms	112764 KiB

tracks

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
using namespace __gnu_pbds;
using ll = long long;
using ull = unsigned ll;
template<typename T> using vt = vector<T>;
using vi = vt<int>;
using vvi = vt<vi>;
using ii = pair<int, int>;
using vii = vt<ii>;
struct chash {
    static ull hash_f(ull x) {x += 0x9e3779b97f4a7c15; x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9; x = (x ^ (x >> 27)) * 0x94d049bb133111eb; return x ^ (x >> 31);}
    size_t operator()(ull x) const {static const ull RANDOM = chrono::steady_clock::now().time_since_epoch().count();return hash_f(x + RANDOM);}
};
struct iihash {
    template <class T1, class T2>
    size_t operator () (const pair<T1,T2> &p) const {auto h1 = hash<T1>{}(p.first);auto h2 = hash<T2>{}(p.second);return h1 ^ h2;}
};
template<class T1, class T2, class T3> using ii_umap = gp_hash_table<pair<T1,T2>,T3,iihash>;
template<class T1, class T2> using f_umap = gp_hash_table<T1,T2,chash>;
template<class T1, class T2> using o_umap = gp_hash_table<T1,T2>;
#define sqr(x) (x)*(x)
#define all(x) begin(x), end(x)
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) (int)(x).size()
#define debug(x) cerr << #x << " -> " << x << '\n'
#define F first
#define S second
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define eb emplace_back
const int inf = 1e9 + 7;
const ll infll = 1e18 + 10;
template <typename T> inline T fgcd(T a, T b) {while(b) swap(b, a %= b); return a;}
ll fpow(ll a, ll b) {ll o = 1; for(;b;b >>= 1) {if(b & 1) o = o * a;a = a * a;} return o;}
ll fpow(ll a, ll b, ll m) {ll o = 1; a %= m; for(;b;b >>= 1) {if(b & 1) o = o * a % m;a = a * a % m;} return o;}
template<class T> void uniq(vt<T> &a) {sort(all(a));a.resize(unique(all(a)) - a.begin());}
void setIO(string name = "", string inp = "inp", string out = "out") {
    cin.tie(0)->sync_with_stdio(0);
    if(sz(name)) {
        if(sz(inp)) freopen((name+"."+inp).c_str(), "r", stdin);
        if(sz(out)) freopen((name+"."+out).c_str(), "w", stdout);
    }
}
int n,m,td[]={0,0,1,-1},tc[]={1,-1,0,0},ans;
int main() {
    setIO();
    cin >> n >> m;
    vt<vt<char>> a(n, vt<char>(m));
    for(auto &i : a)
        for(char &j : i) cin >> j;
    deque<ii> q;
    vvi d(n, vi(m));
    q.pb(mp(0,0));
    d[0][0] = 1;
    while(!q.empty()) {
        ii u = q.front();
        q.pop_front();
        ans = max(ans, d[u.F][u.S]);
        for(int i = 0; i < 4; i++) {
            int ei = u.F + td[i], ej = u.S + tc[i];
            if(ei >= 0 && ej >= 0 && ei < n && ej < m && !d[ei][ej] && a[ei][ej] != '.') {
                if(a[ei][ej] == a[u.F][u.S]) {
                    d[ei][ej] = d[u.F][u.S];
                    q.push_front(mp(ei,ej));
                }
                else {
                    d[ei][ej] = d[u.F][u.S] + 1;
                    q.push_back(mp(ei,ej));
                }
            }
        }
    }
    cout << ans;
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

tracks.cpp: In function 'void setIO(std::string, std::string, std::string)':
tracks.cpp:43:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   43 |         if(sz(inp)) freopen((name+"."+inp).c_str(), "r", stdin);
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:44:28: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   44 |         if(sz(out)) freopen((name+"."+out).c_str(), "w", stdout);
      |                     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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