uva 816 Abbott的复仇

#include <bits/stdc++.h>
using namespace std;


struct Node
{
    int r,c,dir;
    Node (int r=0,int c=0,int dir = 0) : r(r),c(c),dir(dir) {}
};

const int Maxn = 10;
const char* dirs = "NESW";
const char* turns = "FLR";

int dir_id(char c)
{
    return strchr(dirs,c) - dirs;
}

int turn_id(int c)
{
    return strchr(turns,c) - turns;
}

const int dr[] = {-1,0,1,0};
const int dc[] = {0,1,0,-1};

Node walk(const Node& u,int turn)
{
    int dir = u.dir;
    if(turn==1) dir = (dir - 1 + 4)%4;  ///向左转
    if(turn==2) dir = (dir+ 1)%4;       ///向右转
    return Node(u.r+dr[dir],u.c+dc[dir],dir);
}

bool inside(int r,int c)
{
    if(r>=1&&r<=9&&c>=1&&c<=9)
        return true;
    else return false;
}

int has_edge[Maxn][Maxn][4][3];
int r0,c0,r1,c1,r2,c2,dir;
bool read()
{
    char s[99],s2[99];
    if(scanf("%s%d%d%s%d%d",s,&r0,&c0,s2,&r2,&c2)!=6) return false;

    puts(s);
    dir = dir_id(s2[0]);
    r1 = r0 + dr[dir];
    c1 = c0 + dc[dir];

    memset(has_edge,0,sizeof(has_edge));
    for(;;)
    {
        int r,c;
        scanf("%d",&r);
        if(r==0) break;
        scanf("%d",&c);

        while(scanf("%s",s)==1&&s[0]!=‘*‘)
        {

            for(int i=1; i<strlen(s); i++)
            {
                has_edge[r][c][dir_id(s[0])][turn_id(s[i])] = 1;
            }
        }

    }
    return true;

}

int d[Maxn][Maxn][4];
Node p[Maxn][Maxn][4];

void print_ans (Node u)
{
    vector<Node> nodes;
    for(;;)
    {
        nodes.push_back(u);
        if(d[u.r][u.c][u.dir]==0) break;
        u = p[u.r][u.c][u.dir];
    }
    nodes.push_back(Node(r0,c0,dir));

    int cnt = 0;
    for(int i=nodes.size()-1; i>=0; i--)
    {
        if(cnt%10==0) printf(" ");
        printf(" (%d,%d)",nodes[i].r,nodes[i].c);
        cnt++;
        if(cnt%10==0) printf("\n");

    }
    if(nodes.size()%10!=0) puts("");
}

void bfs()
{
    queue<Node> q;
    memset(d, -1, sizeof(d));
    Node u(r1, c1, dir);
    d[u.r][u.c][u.dir] = 0;
    q.push(u);
    while(!q.empty())
    {
        Node u = q.front();
        q.pop();
        if(u.r == r2 && u.c == c2)
        {
            print_ans(u);
            return;
        }
        for(int i = 0; i < 3; i++)
        {
            Node v = walk(u, i);
            if(has_edge[u.r][u.c][u.dir][i] && inside(v.r, v.c) && d[v.r][v.c][v.dir] < 0)
            {
                d[v.r][v.c][v.dir] = d[u.r][u.c][u.dir] + 1;
                p[v.r][v.c][v.dir] = u;
                q.push(v);
            }
        }
    }
    printf("  No Solution Possible\n");
}


int main()
{
    while(read())
    {
        bfs();
    }
    return 0;
}