CCF-CSP题解 201512-3 画图

画图时思路应该清晰一点。我是将坐标\((x,y)\)映射到\(canvas[y][x]\)上。

连线注意\(+\)号的情况，填充写好\(dfs\)就好了。

#include <bits/stdc++.h>
const int maxn = 100;

using namespace std;

int m, n, q;
char canvas[maxn + 5][maxn + 5];

int vis[maxn + 5][maxn + 5];

int dir[4][2] = {{1, 0}, {-1, 0}, {0, 1}, {0, -1}};

void dfs(int x, int y, char c)
{
    if (vis[y][x])
        return;
    vis[y][x] = 1;
    canvas[y][x] = c;
    for (int i = 0; i <= 3; i++)
    {
        int xx = x + dir[i][0], yy = y + dir[i][1];
        if (xx >= 0 && xx <= m - 1 && yy >= 0 && yy <= n - 1 &&
            canvas[yy][xx] != '|' && canvas[yy][xx] != '-' && canvas[yy][xx] != '+')
            dfs(xx, yy, c);
    }
}

int main()
{
    scanf("%d%d%d", &m, &n, &q);
    for (int i = 0; i <= n - 1; i++)
    for (int j = 0; j <= m - 1; j++)
        canvas[i][j] = '.';

    while (q--)
    {
        int op;
        scanf("%d", &op);
        if (op == 0)
        {
            int x1, y1, x2, y2;
            scanf("%d%d%d%d", &x1, &y1, &x2, &y2);
            if (x1 == x2)
            {
                for (int i = min(y1, y2); i <= max(y1, y2); i++)
                {
                    if (canvas[i][x1] == '-' || canvas[i][x1] == '+')
                        canvas[i][x1] = '+';
                    else
                        canvas[i][x1] = '|';
                }
            }
            else
            {
                for (int i = min(x1, x2); i <= max(x1, x2); i++)
                {
                    if (canvas[y1][i] == '|' || canvas[y1][i] == '+')
                        canvas[y1][i] = '+';
                    else
                        canvas[y1][i] = '-';
                }
            }
        }
        else
        {
            int x, y;
            char c[2];
            scanf("%d%d%s", &x, &y, c);
            memset(vis, 0, sizeof(vis));
            dfs(x, y, c[0]);
        }
    }

    for (int i = n - 1; i >= 0; i--)
    {
        for (int j = 0; j <= m - 1; j++)
            printf("%c", canvas[i][j]);
        printf("\n");
    }

    return 0;
}