제출 #386393

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
386393		bytemask	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	1066 ms	243876 KiB

tracks

#include<bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://x...content-available-to-author-only...i.it/splitmix64.c
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
 
    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

#define IOS         ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
#define pb          push_back
#define eb          emplace_back
#define vi          vector<int>
#define vvi         vector<vector<int>>
#define vii         vector<pii>
#define pii         pair<int,int>
#define all(a)      (a).begin(),(a).end()
#define ff          first
#define ss          second
#define sp(n)       setprecision(n)<<fixed
#define endl        '\n' 
#define umap        unordered_map<long long, long long, custom_hash>

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;        

#define trace(...) __f(#__VA_ARGS__, __VA_ARGS__)
template <typename Arg1>
void __f(const char* name, Arg1&& arg1){
    std::cerr << name << " : " << arg1 << endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args){
    const char* comma = strchr(names + 1, ',');std::cerr.write(names, comma - names) << " : " << arg1<<" | ";__f(comma+1, args...);
}
template<typename T, typename U> static inline T amin(T &x, U y) {
    if (y < x)
        x = y;
    return x;
}
template<typename T, typename U> static inline T amax(T &x, U y) {
    if (x < y)
    x = y;
    return x;
}
inline void YN(int f){
    cout<< "NO\0YES" + 3*f << endl;
}
inline void yn(int f){
    cout<< "No\0Yes" + 3*f << endl;
}
inline void setIO(string name) {
    if(name.empty()) return ;
    freopen((name+".in").c_str(),"r",stdin);
    freopen((name+".out").c_str(),"w",stdout);
}

// -------------------Standard Traversal Moves---------------------
vi fx = {1 ,-1 ,0, 0}, fy = {0, 0, -1, 1};
// vi fx = {2, -2, 2, -2,  1, -1, 1, -1}, fy = {1, 1, -1, -1, 2, 2, -2, -2};
// vi fx = {1, 1, 1, -1, -1 , -1, 0, 0}, fy = {1, -1, 0, 1, -1, 0, 1, -1};
// ----------------------------------------------------------------

// #define int         long long
const long long INF = LLONG_MAX/2;
const int inf = INT_MAX/2;
const int N = 4000 + 5, K = 67, MOD = 1000000007;
string mat[N];
int d[N][N], vis[N][N];
void solve(){
    int n,m;
    cin>>n>>m;
    for(int i=0; i<n; i++){
        cin>>mat[i];
    }
    for(int i=0; i<N; i++) for(int j=0; j<N; j++) d[i][j] = inf;
    d[0][0] = 1;
    deque<pii> dq;
    dq.push_back(make_pair(0,0));
    int ans = 0;
    while(!dq.empty()){
        pii cur = dq.front();
        dq.pop_front();
        int cx = cur.ff, cy = cur.ss;
        if(vis[cx][cy]) continue;
        vis[cx][cy] = 1;
        amax(ans, d[cx][cy]);
        for(int i=0; i<4; i++){
            int nx = cx + fx[i], ny = cy + fy[i];
            if(nx<0 || nx>=n || ny<0 || ny>=m) continue;
            if(vis[nx][ny] || mat[nx][ny]=='.') continue;
            int dis = (mat[nx][ny] != mat[cx][cy]);
            d[nx][ny] = min(d[cx][cy] + dis, d[nx][ny]);
            if(dis) dq.push_back(make_pair(nx,ny));
            else dq.push_front(make_pair(nx,ny));
        }
    }
    cout<<ans<<endl;
}
int32_t main()
{
    IOS;
    string filename = "";
    setIO(filename);
    int TESTS=1;
    // cin>>TESTS;
    while(TESTS--)
    {
        solve();
    }
    // cerr << "Time elapsed: " << 1.0 * clock() / CLOCKS_PER_SEC << " s.";
    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

tracks.cpp: In function 'void setIO(std::string)':
tracks.cpp:66:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   66 |     freopen((name+".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:67:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   67 |     freopen((name+".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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