oj.uz

Submission #751985

# Submission time Handle Problem Language Result Execution time Memory
751985 2023-06-02T03:05:40 Z cwza Tracks in the Snow (BOI13_tracks) C++17
100 / 100
 1022 ms 147836 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
 
 
void IO(string name = "") {
	cin.tie(0)->sync_with_stdio(0);
	if (name.size()) {
		freopen((name + ".in").c_str(), "r", stdin);
		freopen((name + ".out").c_str(), "w", stdout);
	}
}
 
const int inf = 1e9+7;
vector<string> grid;
int H, W;
 
bool is_valid(int row, int col) {
    if(row>=0 && row<H && col>=0 && col<W && grid[row][col]!='.') return true;
    return false;
}
 
int main() {
    // IO("pcb");
 
    cin >> H >> W;
    grid.resize(H);
    for(int i = 0; i < H; i++) cin >> grid[i];
 
    vector<vector<int>> dist(H, vector<int>(W, inf));
    dist[0][0] = 0;
    deque<tuple<int,int,int>> dq; // d, row, col
    dq.push_back({0, 0, 0});
    while(dq.size()) {
        auto [d, row, col] = dq.front(); dq.pop_front();
        if(d>dist[row][col]) continue;
        pair<int,int> dirs[] = {{0,1},{0,-1},{1,0},{-1,0}};
        for(auto[dirrow, dircol] : dirs) {
            int nrow = row + dirrow;
            int ncol = col + dircol;
            if(is_valid(nrow, ncol)) {
                if(grid[row][col]==grid[nrow][ncol]) { // 0
                    if(dist[row][col]+0<dist[nrow][ncol]) {
                        dist[nrow][ncol] = dist[row][col]+0;
                        dq.push_front({dist[nrow][ncol], nrow, ncol});
                    }
                } else { // 1
                    if(dist[row][col]+1<dist[nrow][ncol]) {
                        dist[nrow][ncol] = dist[row][col]+1;
                        dq.push_back({dist[nrow][ncol], nrow, ncol});
                    }
                }
            }
        }
    }
    int ans = 0;
    for(int i = 0; i < H; i++) {
        for(int j = 0; j < W; j++) {
            if(dist[i][j]<inf) {
                ans = max(ans, dist[i][j]);
            }
        }
    }
    cout << ans+1;
}

Compilation message

tracks.cpp: In function 'void IO(std::string)':
tracks.cpp:9:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
    9 |   freopen((name + ".in").c_str(), "r", stdin);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
tracks.cpp:10:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |   freopen((name + ".out").c_str(), "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
30.0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 19 ms 2004 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 10 ms 1620 KB Output is correct
5 Correct 4 ms 852 KB Output is correct
6 Correct 1 ms 212 KB Output is correct
7 Correct 1 ms 212 KB Output is correct
8 Correct 1 ms 340 KB Output is correct
9 Correct 1 ms 312 KB Output is correct
10 Correct 4 ms 724 KB Output is correct
11 Correct 3 ms 616 KB Output is correct
12 Correct 10 ms 916 KB Output is correct
13 Correct 4 ms 852 KB Output is correct
14 Correct 4 ms 852 KB Output is correct
15 Correct 16 ms 2072 KB Output is correct
16 Correct 20 ms 2068 KB Output is correct
17 Correct 13 ms 1876 KB Output is correct
18 Correct 10 ms 1620 KB Output is correct

Subtask #2
70.0 / 70.0

# Verdict Execution time Memory Grader output
1 Correct 3 ms 724 KB Output is correct
2 Correct 71 ms 10312 KB Output is correct
3 Correct 510 ms 108920 KB Output is correct
4 Correct 129 ms 25900 KB Output is correct
5 Correct 307 ms 55840 KB Output is correct
6 Correct 993 ms 128440 KB Output is correct
7 Correct 3 ms 724 KB Output is correct
8 Correct 3 ms 724 KB Output is correct
9 Correct 3 ms 692 KB Output is correct
10 Correct 2 ms 488 KB Output is correct
11 Correct 3 ms 724 KB Output is correct
12 Correct 1 ms 340 KB Output is correct
13 Correct 72 ms 10280 KB Output is correct
14 Correct 41 ms 6476 KB Output is correct
15 Correct 35 ms 7116 KB Output is correct
16 Correct 36 ms 4152 KB Output is correct
17 Correct 184 ms 27960 KB Output is correct
18 Correct 138 ms 27592 KB Output is correct
19 Correct 130 ms 25776 KB Output is correct
20 Correct 114 ms 23756 KB Output is correct
21 Correct 303 ms 57708 KB Output is correct
22 Correct 305 ms 55776 KB Output is correct
23 Correct 358 ms 47804 KB Output is correct
24 Correct 282 ms 56684 KB Output is correct
25 Correct 668 ms 108952 KB Output is correct
26 Correct 847 ms 147836 KB Output is correct
27 Correct 888 ms 136024 KB Output is correct
28 Correct 1022 ms 128412 KB Output is correct
29 Correct 994 ms 125140 KB Output is correct
30 Correct 963 ms 132384 KB Output is correct
31 Correct 768 ms 63424 KB Output is correct
32 Correct 881 ms 134248 KB Output is correct