Submission #79781

#	Time	Username	Problem	Language	Result	Execution time	Memory
79781		antimirage	Dango Maker (JOI18_dango_maker)	C++17	13 / 100	72 ms	71352 KiB

dango_maker

#include <bits/stdc++.h>

#define pb emplace_back

using namespace std;

const int N = 3005;

int n, m, d[2][N][N], sz, u[3000005], wh, bl, ans,  used[3000005], dp[3000005][2];

char ar[N][N];

vector <int> g[3000005], vec;

void dfs1 (int v, int color)
{
    if (color == 0) wh++;
    else bl++;
    u[v] = 1;

    for (auto to : g[v])
    {
        if (!u[to])
            dfs1(to, color ^ 1);
    }
}
bool fl;

void check(int v, int p)
{
    vec.push_back(v);

    used[v] = 1;

    for (auto to : g[v])
    {
        if (to == p) continue;
        if (used[to])
            fl = false;
        else
            check(to, v);
    }
}
void dfs2 (int v, int p)
{
    u[v] = 1;

    int sum1 = 1, sum2 = 0;

    for (auto to : g[v])
    {
        if (to == p) continue;
        dfs2(to, v);

        sum1 += dp[to][0];
        sum2 += max(dp[to][0], dp[to][1]);
    }
    dp[v][0] = sum2;
    dp[v][1] = sum1;
}
main()
{
    cin >> n >> m;

    for (int i = 1; i <= n; i++)
    {
        scanf("\n");
        for (int j = 1; j <= m; j++)
            scanf("%c", &ar[i][j]);
    }
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            if ( j + 2 <= m && ar[i][j] == 'R' && ar[i][j + 1] == 'G' && ar[i][j + 2] == 'W' )
                d[0][i][j] = ++sz;
            if ( i + 2 <= n && ar[i][j] == 'R' && ar[i + 1][j] == 'G' && ar[i + 2][j] == 'W')
                d[1][i][j] = ++sz;
        }
    }
    for (int i = 1; i <= n; i++)
    {
        for (int j = 1; j <= m; j++)
        {
            if ( d[0][i][j] )
            {
                if (d[1][i][j])
                    g[ d[0][i][j] ].pb( d[1][i][j] );

                if (d[1][i - 1][j + 1])
                    g[ d[0][i][j] ].pb( d[1][i - 1][j + 1] );

                if (d[1][i - 2][j + 2])
                    g[ d[0][i][j] ].pb( d[1][i - 2][j + 2] );
            }
            if ( d[1][i][j] )
            {
                if (d[0][i][j])
                    g[ d[1][i][j] ].pb( d[0][i][j] );

                if (d[0][i + 1][j - 1])
                    g[ d[1][i][j] ].pb( d[0][i + 1][j - 1] );

                if (d[0][i + 2][j - 2])
                    g[ d[1][i][j] ].pb( d[0][i + 2][j - 2] );
            }
        }
    }
    for (int i = 1; i <= sz; i++)
    {
        if (u[i]) continue;
        vec.clear();
        fl = 1;

        check(i, 0);

        if (fl)
        {
            dfs2(i, 0);
            ans += max(dp[i][0], dp[i][1]);
        }
        else
        {
            wh = bl = 0;
            dfs1(i, 0);
            ans += max( wh, bl );
        }
        for (auto to : vec)
            used[to] = dp[to][0] = dp[to][1] = 0;
    }
    cout << ans << endl;
}
/**
7 7
RRRRRGW
RRRRGWR
RRRGWRR
RRGRRRR
RGWRRRR
GWRRRRR
WRRRRRR
**/

Compilation message (stderr)

dango_maker.cpp:61:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main()
      ^
dango_maker.cpp: In function 'int main()':
dango_maker.cpp:67:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("\n");
         ~~~~~^~~~~~
dango_maker.cpp:69:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
             scanf("%c", &ar[i][j]);
             ~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 0 / 20
• Subtask 3: 0 / 67