天梯赛L2题解（045-048）

L2-045 堆宝塔

不是很复杂的模拟，依照题意写就行了

#include <bits/stdc++.h>
using namespace std;
#define int long long

void ylh_() {
    int n;
    cin >> n;
    vector<int> a(n + 1);
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
    }
    stack<int> st1, st2;
    int ans1 = 0, ans2 = 0;
    for (int i = 1; i <= n; ++i) {
        if (st1.empty()) {
            st1.push(a[i]);
        } else {
            if (a[i] < st1.top()) {
                st1.push(a[i]);
            } else {
                if (st2.empty()) {
                    st2.push(a[i]);
                } else {
                    if (a[i] > st2.top()) {
                        st2.push(a[i]);
                    } else {
                        ++ans1;
                        ans2 = max((int)st1.size(), ans2);
                        while (!st1.empty()) {
                            st1.pop();
                        }
                        while (!st2.empty() && st2.top() > a[i]) {
                            st1.push(st2.top());
                            st2.pop();
                        }
                        st1.push(a[i]);
                    }
                }
            }
        }
    }
    if (st2.size()) {
        ++ans1;
        ans2 = max((int)st2.size(), ans2);
    }
    if (st1.size()) {
        ++ans1;
        ans2 = max((int)st1.size(), ans2);
    }
    cout << ans1 << ' ' << ans2;
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    // cin >> T;
    while (T--) {
        ylh_();
    }
}

L2-046 天梯赛的赛场安排

题目依旧讲不清白
每个学校的监考人数是学校的学生分配去的考场数
因为只要遇见大于c的就直接开一个考场塞满，对答案没影响，这一部分可以优化掉，就不会超时

#include <bits/stdc++.h>
using namespace std;
#define int long long
using PII = pair<int, int>;

void ylh_() {
    int n, c;
    cin >> n >> c;
    int ans = 0;
    vector<string> name(n + 1);
    vector<PII> num(n + 1);
    vector<int> cnt(n + 1);
    for (int i = 1; i <= n; ++i) {
        cin >> name[i] >> num[i].first;
        cnt[i] += num[i].first / c;
        ans += cnt[i];
        num[i].first %= c;
        num[i].second = i;
    }
    vector<int> Room;
    sort(num.begin() + 1, num.end(), greater<PII>());
    for (int i = 1; i <= n; ++i) {
        auto [val, idx] = num[i];
        if (val == 0)
            continue;
        int find = 0;
        for (auto& person : Room) {
            if (person + val <= c) {
                person += val;
                find = 1;
                cnt[idx]++;
                break;
            }
        }
        if (!find) {
            Room.push_back(val);
            cnt[idx]++;
        }
    }
    for (int i = 1; i <= n; ++i) {
        cout << name[i] << ' ' << cnt[i] << '\n';
    }
    cout << ans + Room.size();
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    // cin >> T;
    while (T--) {
        ylh_();
    }
}

L2-047 锦标赛

#include <bits/stdc++.h>
using namespace std;
#define int long long
using PII = pair<int, int>;

void ylh_() {
    int t;
    cin >> t;
    vector<PII> tr(1 << 20); // PII第一维表示败者，二维表示胜者，按照每场比赛为节点建立完美二叉树
    for (int i = 1; i <= t; ++i) {
        for (int j = (1 << (t - i)); j <= (1 << (t - i + 1)) - 1; ++j) {
            cin >> tr[j].first;
        }
    }
    cin >> tr[1].second;
    auto dfs = [&](auto&& dfs, int u) -> bool {
        if (u > ((1 << t) - 1))
            return true;
        if (tr[u].first > tr[u].second) {
            return false;
        }
        tr[u << 1].second = tr[u].first;
        tr[(u << 1) + 1].second = tr[u].second;
        if (dfs(dfs, u << 1) && dfs(dfs, (u << 1) + 1))
            return true;
        swap(tr[u << 1].second, tr[(u << 1) + 1].second);
        if (dfs(dfs, u << 1) && dfs(dfs, (u << 1) + 1))
            return true;
        return false;
    };
    if (dfs(dfs, 1)) {
        for (int i = (1 << t - 1); i <= (1 << t) - 1; ++i) {
            if (i != (1 << t) - 1) {
                cout << tr[i].first << ' ' << tr[i].second << ' ';
            } else {
                cout << tr[i].first << ' ' << tr[i].second;
            }
        }
    } else {
        cout << "No Solution";
    }
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    // cin >> T;
    while (T--) {
        ylh_();
    }
}

L2-048 寻宝图

纯血经典搜索题

#include <bits/stdc++.h>
using namespace std;
#define int long long

int dx[4] = { 0, 1, 0, -1 };
int dy[4] = { 1, 0, -1, 0 };

void ylh_() {
    int n, m;
    cin >> n >> m;
    vector<string> a(n + 1);
    vector<vector<int>> vis(n + 1, vector<int>(m + 1));
    int find = 0;
    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
        a[i] = " " + a[i];
    }
    auto dfs = [&](auto&& dfs, int x, int y) -> void {
        if (vis[x][y])
            return;
        if (a[x][y] != '1') {
            find = 1;
        }
        vis[x][y] = 1;
        for (int i = 0; i < 4; ++i) {
            int nx = dx[i] + x;
            int ny = dy[i] + y;
            if (nx < 1 || nx > n || ny < 1 || ny > m)
                continue;
            if (a[nx][ny] == '0') {
                continue;
            }
            dfs(dfs, nx, ny);
        }
    };
    int ans1 = 0, ans2 = 0;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            if (a[i][j] != '0' && !vis[i][j]) {
                ++ans1;
                find = 0;
                dfs(dfs, i, j);
                ans2 += find;
            }
        }
    }
    cout << ans1 << ' ' << ans2;
}

int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    // cin >> T;
    while (T--) {
        ylh_();
    }
}