oj.uz

Submission #418524

# Submission time Handle Problem Language Result Execution time Memory
418524 2021-06-05T12:44:48 Z gsc2001 Tracks in the Snow (BOI13_tracks) C++17
100 / 100
 658 ms 130868 KB 
#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define ld long double
#define f(i, l, r) for (int i = l; i <= r; i++)
#define debug(x) cout << #x << '=' << (x) << endl
#define pb push_back
#define all(x) x.begin(), x.end()
#define sz(x) (ll)(x).size()
#define ff first
#define ss second

using PLL = pair<ll, ll>;
using VL = vector<ll>;
using VLL = vector<pair<ll, ll>>;

// -------------------------------------------------------------------------------
constexpr int mod = 1e9 + 7;

void setIO(const string &name = "") {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if (sz(name)) {
        freopen((name + ".in").c_str(), "r", stdin);
        freopen((name + ".out").c_str(), "w", stdout);
    }
}

// -------------------------------------------------------------------------------
// ------------------------Template End ------------------------------------------
// -------------------------------------------------------------------------------
string grid[4004];
int dx[4]{1, -1, 0, 0}, dy[4]{0, 0, 1, -1};
int n, m;

bool valid(int x, int y) {
    return x >= 0 and x < n and y >= 0 and y < m and grid[x][y] != '.';
}

int dist[4004][4004];

int main() {
    setIO();
    cin >> n >> m;
    for (int i = 0; i < n; i++) {
        cin >> grid[i];
    }
    deque<pair<int, int>> q;
    q.push_back({0, 0});
    int ans = 1;
    dist[0][0] = 1;
    while (q.size()) {
        auto curr = q.front();
        q.pop_front();
        ans = max(ans, dist[curr.ff][curr.ss]);

        for (int i = 0; i < 4; i++) {
            int x = curr.ff + dx[i], y = curr.ss + dy[i];
            if (valid(x, y) and dist[x][y] == 0) {
                if (grid[curr.ff][curr.ss] == grid[x][y]) {
                    dist[x][y] = dist[curr.ff][curr.ss];
                    q.push_front({x, y});
                } else {
                    dist[x][y] = dist[curr.ff][curr.ss] + 1;
                    q.push_back({x, y});
                }
            }
        }
    }
    cout << ans;

    return 0;
}

Compilation message

tracks.cpp: In function 'void setIO(const string&)':
tracks.cpp:25:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   25 |         freopen((name + ".in").c_str(), "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:26:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   26 |         freopen((name + ".out").c_str(), "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 3788 KB Output is correct
2 Correct 1 ms 460 KB Output is correct
3 Correct 1 ms 588 KB Output is correct
4 Correct 7 ms 3532 KB Output is correct
5 Correct 3 ms 1996 KB Output is correct
6 Correct 1 ms 460 KB Output is correct
7 Correct 1 ms 572 KB Output is correct
8 Correct 1 ms 716 KB Output is correct
9 Correct 1 ms 844 KB Output is correct
10 Correct 3 ms 1612 KB Output is correct
11 Correct 2 ms 1484 KB Output is correct
12 Correct 5 ms 2124 KB Output is correct
13 Correct 3 ms 1996 KB Output is correct
14 Correct 3 ms 1996 KB Output is correct
15 Correct 10 ms 3660 KB Output is correct
16 Correct 12 ms 3880 KB Output is correct
17 Correct 8 ms 3660 KB Output is correct
18 Correct 7 ms 3532 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 10 ms 15968 KB Output is correct
2 Correct 37 ms 11852 KB Output is correct
3 Correct 201 ms 75456 KB Output is correct
4 Correct 66 ms 29344 KB Output is correct
5 Correct 167 ms 51436 KB Output is correct
6 Correct 640 ms 109948 KB Output is correct
7 Correct 12 ms 16588 KB Output is correct
8 Correct 11 ms 15980 KB Output is correct
9 Correct 2 ms 716 KB Output is correct
10 Correct 1 ms 460 KB Output is correct
11 Correct 11 ms 16332 KB Output is correct
12 Correct 2 ms 1100 KB Output is correct
13 Correct 39 ms 11808 KB Output is correct
14 Correct 22 ms 7920 KB Output is correct
15 Correct 20 ms 10268 KB Output is correct
16 Correct 21 ms 4912 KB Output is correct
17 Correct 102 ms 25060 KB Output is correct
18 Correct 85 ms 32088 KB Output is correct
19 Correct 71 ms 29320 KB Output is correct
20 Correct 51 ms 22468 KB Output is correct
21 Correct 125 ms 50472 KB Output is correct
22 Correct 168 ms 51452 KB Output is correct
23 Correct 194 ms 42308 KB Output is correct
24 Correct 128 ms 47444 KB Output is correct
25 Correct 493 ms 96460 KB Output is correct
26 Correct 367 ms 130868 KB Output is correct
27 Correct 500 ms 123136 KB Output is correct
28 Correct 658 ms 109936 KB Output is correct
29 Correct 640 ms 108460 KB Output is correct
30 Correct 582 ms 112328 KB Output is correct
31 Correct 524 ms 72076 KB Output is correct
32 Correct 436 ms 108320 KB Output is correct