oj.uz

Submission #727910

# Submission time Handle Problem Language Result Execution time Memory
727910 2023-04-21T14:43:03 Z ace_in_the_hole Tracks in the Snow (BOI13_tracks) C++17
100 / 100
 668 ms 130888 KB 
#include<bits/stdc++.h>
using namespace std;
//https://oj.uz/problem/view/BOI13_tracks
typedef long long Int;

const int N = 4005;
char board[N][N];
int dist[N][N];
using Cell = pair<int,int>;
#define x first
#define y second

#define all(v) (v).begin(), (v).end()
#define cst(T) const T&

template<class A, class B> bool umin(A& var, cst(B) val) {
    return (val < var) ? (var = val, true) : false;
}
template<class A, class B> bool umax(A& var, cst(B) val) {
    return (var < val) ? (var = val, true) : false;
}

const int INF = 1e9;
const int dx[] {-1,+1, 0, 0};
const int dy[] { 0, 0,-1,+1};

void solve() 
{
    int hei, wid;
    cin >> hei >> wid;
    for (int i = 1; i <= hei; i++)
        for (int j = 1; j <= wid; j++) {
            dist[i][j] = INF;
            cin >> board[i][j];
        }
    deque<Cell> bfs;
    bfs.push_front(Cell(1,1));
    dist[1][1] = 1;
    int ans = 0;
    while (!bfs.empty()) {
        auto u = bfs.front(); bfs.pop_front();
        umax(ans, dist[u.x][u.y]);
        for (int d = 0; d < 4; d++) {
            Cell v(u.x + dx[d], u.y + dy[d]);
            if (min(v.x,v.x) < 1 or v.x > hei or v.y > wid) continue;
            if (board[v.x][v.y] == '.') continue;
            int edge = (board[v.x][v.y] != board[u.x][u.y]);
            if (umin(dist[v.x][v.y], dist[u.x][u.y] + edge))
                edge ? bfs.push_back(v) : bfs.push_front(v);
        }
    }
    cout << ans;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);

    #define task "WF"
    if (fopen(task".inp", "r")) {
        freopen(task".inp", "r", stdin);
        freopen(task".out", "w", stdout);
    }
    solve();
}

Compilation message

tracks.cpp: In function 'int main()':
tracks.cpp:62:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   62 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:63:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   63 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 13 ms 5460 KB Output is correct
2 Correct 1 ms 468 KB Output is correct
3 Correct 1 ms 724 KB Output is correct
4 Correct 8 ms 5204 KB Output is correct
5 Correct 4 ms 3028 KB Output is correct
6 Correct 1 ms 468 KB Output is correct
7 Correct 1 ms 724 KB Output is correct
8 Correct 1 ms 724 KB Output is correct
9 Correct 1 ms 1108 KB Output is correct
10 Correct 3 ms 2516 KB Output is correct
11 Correct 3 ms 2132 KB Output is correct
12 Correct 5 ms 3032 KB Output is correct
13 Correct 3 ms 3028 KB Output is correct
14 Correct 4 ms 3024 KB Output is correct
15 Correct 12 ms 5552 KB Output is correct
16 Correct 13 ms 5460 KB Output is correct
17 Correct 11 ms 5220 KB Output is correct
18 Correct 8 ms 5204 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 30932 KB Output is correct
2 Correct 51 ms 17828 KB Output is correct
3 Correct 332 ms 86012 KB Output is correct
4 Correct 98 ms 33600 KB Output is correct
5 Correct 219 ms 67028 KB Output is correct
6 Correct 668 ms 99788 KB Output is correct
7 Correct 15 ms 32280 KB Output is correct
8 Correct 16 ms 30932 KB Output is correct
9 Correct 3 ms 724 KB Output is correct
10 Correct 4 ms 468 KB Output is correct
11 Correct 14 ms 31700 KB Output is correct
12 Correct 2 ms 1616 KB Output is correct
13 Correct 52 ms 17900 KB Output is correct
14 Correct 31 ms 11852 KB Output is correct
15 Correct 27 ms 13132 KB Output is correct
16 Correct 23 ms 6620 KB Output is correct
17 Correct 152 ms 36164 KB Output is correct
18 Correct 106 ms 35740 KB Output is correct
19 Correct 101 ms 33484 KB Output is correct
20 Correct 82 ms 30956 KB Output is correct
21 Correct 223 ms 70184 KB Output is correct
22 Correct 213 ms 67860 KB Output is correct
23 Correct 237 ms 56900 KB Output is correct
24 Correct 203 ms 69368 KB Output is correct
25 Correct 503 ms 88820 KB Output is correct
26 Correct 431 ms 130888 KB Output is correct
27 Correct 563 ms 107404 KB Output is correct
28 Correct 660 ms 102996 KB Output is correct
29 Correct 624 ms 102776 KB Output is correct
30 Correct 601 ms 101712 KB Output is correct
31 Correct 480 ms 73544 KB Output is correct
32 Correct 493 ms 101860 KB Output is correct