Submission #1107045

#	Time	Username	Problem	Language	Result	Execution time	Memory
1107045		TgX_2	Tracks in the Snow (BOI13_tracks)	C++17	100 / 100	610 ms	238632 KiB

tracks

/*-----------------------------
        Author : TgX.2
       11Ti - K28 - CHV
-----------------------------*/

#include <bits/stdc++.h>
using   namespace std;

#ifdef TGX 
#include "debug.h"
#else 
#define debug(...)
#endif 

#define FOR(i, a, b)       for (int i = (a), _b = (b); i <= _b; i += 1)
#define FORD(i, a, b)      for (int i = (a), _b = (b); i >= _b; i -= 1)

#define fi                 first
#define se                 second
#define pb                 push_back
#define len(x)             (int)((x).size())
#define all(x)             (x).begin(), (x).end()

#define _                  << " " <<
#define __                 << "\n"
#define ___                << " "

#define ______________TgX______________ main()
#define int                long long
#define intmax             1e9
#define intmin            -1e9
#define llongmax           1e18
#define llongmin          -1e18
#define memo(a, val)       memset((a), (val), sizeof((a)))

struct custom {
    static uint64_t splitmix64(uint64_t x) {
        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);
    }
};
template<class T1, class T2> using cmap = unordered_map<T1, T2, custom>;

template<typename T1, typename T2> 
bool mini(T1 &a, T2 b)
    {if (a > b) a = b; else return 0; return 1;}

template<typename T1, typename T2> 
bool maxi(T1 &a, T2 b)
    {if (a < b) a = b; else return 0; return 1;}
/*-----------------------------*/

const int dx[5] = {0, 1, 0, -1};
const int dy[5] = {1, 0, -1, 0};

const int maxn = 4007;
int n, m, dis[maxn][maxn];
char a[maxn][maxn];


void process() {
    cin >> n >> m;
    FOR(i, 1, n) FOR(j, 1, m)
        cin >> a[i][j];

    deque<pair<int, int>> q;
    q.push_back({1, 1});

    int ans = 0;

    dis[1][1] = 1;
    while(!q.empty()) {
        pair<int, int> top = q.front(); q.pop_front();
        int x = top.fi, y = top.se;
        maxi(ans, dis[x][y]);

        FOR(i, 0, 3) {
            int xx = x + dx[i];
            int yy = y + dy[i];

            if (xx < 1 or xx > n or yy < 1 or yy > m or a[xx][yy] == '.') continue;

            if (dis[xx][yy] == 0) {
                if (a[xx][yy] == a[x][y]) {
                    dis[xx][yy] = dis[x][y];
                    q.push_front({xx, yy});
                } else {
                    dis[xx][yy] = dis[x][y] + 1;
                    q.push_back({xx, yy});
                }
            }
        }
    }

    cout << ans;
}



/*-----------------------------*/
______________TgX______________ {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);  
    if (fopen("temp.inp", "r")) {
        freopen("temp.inp", "r", stdin);
        freopen("temp.out", "w", stdout);
    }
    process();
    cerr << "Time: " << 1.0 * clock() / CLOCKS_PER_SEC << " s." __ ;
}


/*==============================+
|INPUT                          |
--------------------------------|

================================+
|OUTPUT                         |
--------------------------------|

===============================*/

Compilation message (stderr)

tracks.cpp:28:41: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   28 | #define ______________TgX______________ main()
      |                                         ^~~~
tracks.cpp:108:1: note: in expansion of macro '______________TgX______________'
  108 | ______________TgX______________ {
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp: In function 'int main()':
tracks.cpp:112:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |         freopen("temp.inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:113:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |         freopen("temp.out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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