solution.cpp

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <queue>
#include <set>
using namespace std;

#define N 30
#define M 50

char map[N][M];
int dir[4][2] = {{1, 0}, {0, -1}, {0, 1}, {-1, 0}}; //D<L<R<U
char ch[4] = {'D', 'L', 'R', 'U'};
int vis[N][M] = {0};

struct point
{
    int x, y;
    string road;
    point(int a, int b)
    {
        x = a;
        y = b;
    }
};

void bfs()
{
    queue<point> q;
    point p(0, 0);
    p.road = "";
    q.push(p);
    vis[0][0] = 1;
    while (!q.empty())
    {
        point t = q.front();
        q.pop();
        if (t.x == N - 1 && t.y == M - 1)
        {
            cout << t.road << endl;
            break;
        }
        for (int i = 0; i < 4; i++)
        {
            int dx = t.x + dir[i][0];
            int dy = t.y + dir[i][1];
            if (dx >= 0 && dx < N && dy >= 0 && dy < M)
            {
                if (map[dx][dy] == '0' && !vis[dx][dy])
                {
                    point tt(dx, dy);
                    tt.road = t.road + ch[i]; //记录路径
                    q.push(tt);
                    vis[dx][dy] = 1;
                }
            }
        }
    }
}

int main()
{
    for (int i = 0; i < N; i++)
    {
        for (int j = 0; j < M; j++)
            scanf("%c", &map[i][j]);
        getchar(); //读掉回车
    }
    bfs();
    return 0;
}