D-Points Construction Problem

晚點時間再更新具體思路

思路

1. 先放一個\(2*2\)的矩陣
2. 向上/右擴充套件
3. 完善矩陣
4. 向右/上擴充套件
5. 完善矩陣
6. 重複2-6直到足夠
7. 輸出

AC code

#include <bits/stdc++.h>

using namespace std;

bool flag[60][60];

void print(int n) {
    if (n < 0) {
        cout << "No" << endl;
        return;
    }
    cout << "Yes" << endl;
    while (n) {
        cout << n * 100 << " " << n * 100 << endl;
        n--;
    }
    for (int i = 0; i < 60; ++i)
        for (int j = 0; j < 60; ++j)
            if (flag[i][j])
                cout << i + 1 << " " << j + 1 << endl;
}

void solve() {
    int T;
    cin >> T;
    for (int ts = 0; ts < T; ++ts) {
        int n, m;
        cin >> n >> m;
        int target = (n * 4 - m) / 2;
        if ((n * 4 - m) & 1) {
            n = -1;
            print(n);
            continue;
        }
        memset(flag, 0, sizeof(flag));

        if (target < 4) {
            int x = 2;
            flag[1][1] = true;
            n--;

            while (target && n >= 0) {
                flag[x][1] = true;
                x++;
                target--;
                n--;
            }
            print(n);
            continue;
        }
        flag[1][1] = flag[1][2] = flag[2][1] = flag[2][2] = true;
        n -= 4;
        target -= 4;

        int l = 3, r = 3;
        while (target > 2) {
            // 右擴充套件
            flag[1][l] = true;
            flag[2][l] = true;
            l++;
            target -= 3;
            n -= 2;

            int len = 3;
            while (len < r && target > 1) {
                flag[len][l - 1] = true;
                target -= 2;
                n--;
                len++;
            }

            if (target > 2) {
                // 上擴充套件
                flag[r][1] = true;
                flag[r][2] = true;
                r++;
                target -= 3;
                n -= 2;

                len = 3;
                while (len < l && target > 1) {
                    flag[r - 1][len] = true;
                    target -= 2;
                    n--;
                    len++;
                }
            }
        }

        if (target == 2) {
            n -= 2;
            flag[0][1] = true;
            flag[1][0] = true;
        } else if (target == 1) {
            n -= 1;
            flag[0][1] = true;
        }
        print(n);
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
#ifdef ACM_LOCAL
    freopen("in.txt", "r", stdin);
    freopen("out.txt", "w", stdout);
    int test_index_for_debug = 1;
    char acm_local_for_debug;
    while (cin >> acm_local_for_debug) {
        if (acm_local_for_debug == '$') exit(0);
        cin.putback(acm_local_for_debug);
        if (test_index_for_debug > 20) {
            throw runtime_error("Check the stdin!!!");
        }
        auto start_clock_for_debug = clock();
        solve();
        auto end_clock_for_debug = clock();
        cout << "Test " << test_index_for_debug << " successful" << endl;
        cerr << "Test " << test_index_for_debug++ << " Run Time: "
             << double(end_clock_for_debug - start_clock_for_debug) / CLOCKS_PER_SEC << "s" << endl;
        cout << "--------------------------------------------------" << endl;
    }
#else
    solve();
#endif
    return 0;
}