Submission #484886

#	Time	Username	Problem	Language	Result	Execution time	Memory
484886		Olympia	Tracks in the Snow (BOI13_tracks)	C++17	2.19 / 100	1513 ms	1048580 KiB

tracks

#include <vector>
#include <iostream>
#include <cassert>
#include <cmath>
#include <set>
#include <map>
#include <stack>
#include <queue>
#include <set>
#include <algorithm>
#include <iomanip>

using namespace std;
vector<vector<bool>> hasVisited;
vector<string> grid;
int R = 0;
int B = 0;
void dfs (int x, int y) {
    if (hasVisited[x][y]) {
        return;
    }
    hasVisited[x][y] = true;
    R += (grid[x][y] == 'R');
    B += (grid[x][y] == 'F');
    for (int dx = -1; dx <= 1; dx++) {
        for (int dy = -1; dy <= 1; dy++) {
            if (dx + x < 0 || dx + x == hasVisited.size() || dy + y < 0 || dy + y == hasVisited[0].size()) {
                continue;
            }
            if (grid[x + dx][y + dy] != '.') {
                dfs(dx + x, dy + y);
            }
        }
    }
}
int main() {
    int n, m;
    cin >> n >> m;
    hasVisited.resize(n), grid.resize(n);
    for (int i = 0; i < n; i++) {
        hasVisited[i].resize(m);
        cin >> grid[i];
        for (int j = 0; j < m; j++) {
            hasVisited[i][j] = false;
        }
    }
    int ans = 0;
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            if (!hasVisited[i][j] && grid[i][j] != '.') {
                dfs(i, j);
                //cout << R << " " << B << '\n';
                //R = B = 0;
                ans += (bool)R + (bool)B;
            }
        }
    }
    cout << ans;
}

Compilation message (stderr)

tracks.cpp: In function 'void dfs(int, int)':
tracks.cpp:27:38: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::vector<bool> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |             if (dx + x < 0 || dx + x == hasVisited.size() || dy + y < 0 || dy + y == hasVisited[0].size()) {
      |                               ~~~~~~~^~~~~~~~~~~~~~~~~~~~
tracks.cpp:27:83: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<bool>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   27 |             if (dx + x < 0 || dx + x == hasVisited.size() || dy + y < 0 || dy + y == hasVisited[0].size()) {
      |                                                                            ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 30
• Subtask 2: 2.1875 / 70