TOI202105 新手組

Inversion.cpp

#include <bits/stdc++.h>

using namespace std;

void print(const string &s, int start, int end, char dir)
{
    if (dir == '+')
    {
        for (int i = start + 1; i < end; i++)
            cout << s[i];
    }
    else if (dir == '-')
    {
        for (int i = end - 1; i > start; i--)
            cout << s[i];
    }
}

int main()
{
    string s;
    cin >> s;

    vector<int> v_idx;
    for (int i = 0; i < s.length(); i++)
    {
        if (s[i] == '+' || s[i] == '-')
            v_idx.push_back(i);
    }

    if (v_idx.empty())
    {
        cout << s;
        return 0;
    }

    int idx = v_idx[0];
    char dir = '+';
    print(s, -1, idx, dir);
    dir = s[idx];

    for (int i = 1; i < v_idx.size(); i++)
    {
        print(s, idx, v_idx[i], dir);
        idx = v_idx[i];
        dir = s[idx];
    }

    if (idx != s.length() - 1)
        print(s, idx, s.length(), dir);

    return 0;
}

Password.cpp

#include <bits/stdc++.h>

using namespace std;

typedef pair<char, int> PCI;

bool cmp(const PCI &a, const PCI &b)
{
    if (a.second == b.second)
        return a.first < b.first;
    return a.second > b.second;
}

int main()
{
    string s;
    cin >> s;
    map<char, int> char_cnt;
    for (auto &x : s)
    {
        char_cnt[x]++;
    }
    vector<PCI> ans(char_cnt.begin(), char_cnt.end());
    sort(ans.begin(), ans.end(), cmp);
    for (auto &x : ans)
    {
        cout << x.first;
    }
}

Popularity.cpp

#include <bits/stdc++.h>

using namespace std;

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

int main()
{
    int R, C;
    cin >> R >> C;
    int area[R + 5][C + 5] = {0};
    int ans[R + 5][C + 5] = {0};
    for (int i = 1; i <= R; i++)
    {
        for (int j = 1; j <= C; j++)
            cin >> area[i][j];
    }
    for (int i = 0; i <= R + 1; i++)
    {
        area[i][0] = 0;
        area[i][C + 1] = 0;
    }
    for (int j = 0; j <= C + 1; j++)
    {
        area[0][j] = 0;
        area[R + 1][j] = 0;
    }
    memcpy(ans, area, sizeof(ans));
    for (int i = 1; i <= R; i++)
    {
        for (int j = 1; j <= C; j++)
        {
            if (area[i][j] != 0)
                continue;
            int z_cnt = 0;
            int sum = 0;
            for (int k = 0; k < 4; k++)
            {
                int n_x = i + dx[k];
                int n_y = j + dy[k];
                sum += area[n_x][n_y];
                if (!area[n_x][n_y])
                    z_cnt++;
            }
            ans[i][j] = (z_cnt == 4) ? 0 : sum / (4 - z_cnt);
        }
    }
    for (int i = 1; i <= R; i++)
    {
        for (int j = 1; j <= C; j++)
        {
            cout << ans[i][j] << " ";
        }
        cout << endl;
    }
}