Submission #144987

#	Time	Username	Problem	Language	Result	Execution time	Memory
144987		SamAnd	Trapezi (COI17_trapezi)	C++17	0 / 100	1089 ms	376 KiB

trapezi

#include <bits/stdc++.h>
using namespace std;
#define m_p make_pair
const int N = 55;

int n;
char a[N][N];
int s[N];

vector<pair<int, int> > g[N][N];

int u[N][N];

bool c[N][N];
vector<pair<int, int> > v;
int dfs(int x, int y)
{
    v.push_back(m_p(x, y));
    c[x][y] = true;
    for (int i = 0; i < g[x][y].size(); ++i)
    {
        pair<int, int> h = g[x][y][i];
        if (!c[h.first][h.second] && u[x][y] == u[h.first][h.second])
            dfs(h.first, h.second);
    }
}

int stg(int x, int y)
{
    v.clear();
    dfs(x, y);
    for (int i = 0; i < v.size(); ++i)
        c[v[i].first][v[i].second] = false;
    return v.size();
}

void rec(int x, int y)
{
    if (x == 2 * n + 1)
    {
        bool z = true;
        for (int i = 1; i <= 2 * n; ++i)
        {
            for (int j = ((4 * n - 1) - s[i]) / 2 + 1; j <= ((4 * n - 1) - s[i]) / 2 + s[i]; ++j)
            {
                if (a[i][j] == '0')
                {
                    if (stg(i, j) != 3)
                    {
                        z = false;
                        break;
                    }
                }
            }
            if (!z)
                break;
        }
        if (z)
        {
            for (int i = 1; i <= 2 * n; ++i)
            {
                for (int j = ((4 * n - 1) - s[i]) / 2 + 1; j <= ((4 * n - 1) - s[i]) / 2 + s[i]; ++j)
                {
                    cout << u[i][j];
                }
                cout << endl;
            }
            exit(0);
        }
        return;
    }
    if (a[x][y] == '0')
    {
        for (int g = 1; g <= 6; ++g)
        {
            u[x][y] = g;
            if (stg(x, y) > 3)
                continue;
            if (y != ((4 * n - 1) - s[x]) / 2 + s[x])
            {
                rec(x, y + 1);
            }
            else
            {
                rec(x + 1, ((4 * n - 1) - s[x + 1]) / 2 + 1);
            }
        }
        u[x][y] = 0;
    }
    else
    {
        if (y != ((4 * n - 1) - s[x]) / 2 + s[x])
        {
            rec(x, y + 1);
        }
        else
        {
            rec(x + 1, ((4 * n - 1) - s[x + 1]) / 2 + 1);
        }
    }
}

int main()
{
    cin >> n;
    for (int i = 0; i < N; ++i)
    {
        for (int j = 0; j < N; ++j)
            a[i][j] = '-';
    }
    s[1] = 2 * n + 1;
    for (int i = 1; i <= 2 * n; ++i)
    {
        for (int j = ((4 * n - 1) - s[i]) / 2 + 1; j <= ((4 * n - 1) - s[i]) / 2 + s[i]; ++j)
        {
            cin >> a[i][j];
            if (a[i][j] == a[i][j - 1])
            {
                g[i][j].push_back(m_p(i, j - 1));
                g[i][j - 1].push_back(m_p(i, j));
            }
            if (i <= n && j % 2 == 0)
            {
                if (a[i][j] == '0' && a[i - 1][j] == '0')
                {
                    g[i][j].push_back(m_p(i - 1, j));
                    g[i - 1][j].push_back(m_p(i, j));
                }
            }
            if (i > n && j % 2 == 1)
            {
                if (a[i][j] == '0' && a[i - 1][j] == '0')
                {
                    g[i][j].push_back(m_p(i - 1, j));
                    g[i - 1][j].push_back(m_p(i, j));
                }
            }
        }
        if (i < n)
        {
            s[i + 1] = s[i] + 2;
        }
        else if (i == n)
        {
            s[i + 1] = s[i];
        }
        else if (i > n)
        {
            s[i + 1] = s[i] - 2;
        }
    }
    /*cout << endl;
    for (int i = 1; i <= n * 2; ++i)
    {
        for (int j = 0; j < N; ++j)
            cout << a[i][j];
        cout << endl;
    }*/
    for (int i = 1; i <= 3; ++i)
    {
        for (int j = 1; j <= 3; ++j)
        {
            if (a[i][j] == '0')
            {
                if (stg(i, j) % 3 != 0)
                {
                    cout << "nemoguce" << endl;
                    return 0;
                }
            }
        }
    }
    rec(1, ((4 * n - 1) - s[1]) / 2 + 1);
    cout << "nemoguce" << endl;
    return 0;
}

Compilation message (stderr)

trapezi.cpp: In function 'int dfs(int, int)':
trapezi.cpp:20:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < g[x][y].size(); ++i)
                     ~~^~~~~~~~~~~~~~~~
trapezi.cpp:26:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
trapezi.cpp: In function 'int stg(int, int)':
trapezi.cpp:32:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 0; i < v.size(); ++i)
                     ~~^~~~~~~~~~

• Subtask 1: 0 / 6
• Subtask 2: 0 / 17
• Subtask 3: 0 / 18
• Subtask 4: 0 / 22
• Subtask 5: 0 / 37