Description

Submission

• No quick solution, for each one of the 8 directions, find the closest obstacle.

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>

using namespace std;

// Complete the queensAttack function below.
int queensAttack(int n, int k, int r_q, int c_q, vector<vector<int>> obstacles) {
    vector<int> dist(8);   // distance to the queen(min)
    dist[0] = n - c_q;
    dist[1] = min(n - c_q, n - r_q);
    dist[2] = n - r_q;
    dist[3] = min(c_q - 1, n - r_q);
    dist[4] = c_q - 1;
    dist[5] = min(c_q - 1, r_q - 1);
    dist[6] = r_q - 1;
    dist[7] = min(r_q - 1, n - c_q);

    // find the closet ones in each of the 8 directions
    for(int i = 0; i < obstacles.size(); ++i) {
        int r = obstacles[i][0];
        int c = obstacles[i][1];
        int dr = r_q - r;
        int dc = c_q - c;

        if(dr == 0 || dc == 0 || dr == dc || dr == -dc) {
            // right
            if(dr == 0 && dc < 0 && -dc < dist[0] + 1)
                dist[0] = -dc - 1;

            // upper right
            if(dr == dc && dr < 0 && -dr < dist[1] + 1)
                dist[1] = -dr - 1;

            // upper
            if(dc == 0 && dr < 0 && -dr < dist[2] + 1)
                dist[2] = -dr - 1;

            // upper left
            if(dc == -dr && dc > 0 && dc < dist[3] + 1)
                dist[3] = dc - 1;

            // left
            if(dr == 0 && dc > 0 && dc < dist[4] + 1)
                dist[4] = dc -1;

            // lower left
            if(dr == dc && dc > 0 && dc < dist[5] + 1)
                dist[5] = dc - 1;

            // lower
            if(dc == 0 && dr > 0 && dr < dist[6] + 1)
                dist[6] = dr - 1;

            // lower right
            if(dr == -dc && dr > 0 && dr < dist[7] + 1)
                dist[7] = dr - 1;
        }

    }

    // calculate the total
    int total = 0;
    for(int i = 0; i < 8; i++) {
        total += dist[i];
    }
    return total;
}

int main()
{
    int n; cin >> n;
    int k; cin >> k;

    int r_q; cin >> r_q;
    int c_q; cin >> c_q;

    vector<vector<int>> obstacles(k);
    for (int i = 0; i < k; i++) {
        obstacles[i].resize(2);

        for (int j = 0; j < 2; j++) {
            cin >> obstacles[i][j];
        }

        cin.ignore(numeric_limits<streamsize>::max(), '\n');
    }

    int result = queensAttack(n, k, r_q, c_q, obstacles);

    cout << result << "\n";

    return 0;
}