uva 816 Abbott's Revenge

#include<iostream>
#include<cstdio>
#include<vector>
#include<cstring>
#include<queue>
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=100;
const char *dirs="NESW";
const char *turns="FLR";
int have_edge[maxn][maxn][4][3];
int d[maxn][maxn][4];
Node p[maxn][maxn][4];
int r0,c0,dir,r1,c1,r2,c2;
char s[100],s2[100];
int dir_id(char c) {return (int)(strchr(dirs,c)-dirs);}
int turn_id(char c) {return (int)(strchr(turns,c)-turns);}
int dr[4]={-1,0,1,0};
int dc[4]={0,1,0,-1};
Node Walk(const Node &u,int turn)
{
int dir=u.dir;
if(turn==1) dir=(dir+3)%4;
if(turn==2) dir=(dir+1)%4;
return Node(u.r+dr[dir],u.c+dc[dir],dir);
}
bool inside(int r,int c)
{
return r>=1&&r<=9&&c>=1&&c<=9;
}
bool read_case()
{
scanf("%s",s);
if(s[0]=='E'&&s[1]=='N'&&s[2]=='D') return false;
scanf("%d%d%s%d%d",&r0,&c0,s2,&r2,&c2);
printf("%s\n",s);
r1=r0+dr[dir_id(s2[0])];
c1=c0+dc[dir_id(s2[0])];
dir=dir_id(s2[0]);
memset(have_edge,0,sizeof(have_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<(int)strlen(s);i++)
have_edge[r][c][dir_id(s[0])][turn_id(s[i])]=1;
}
return true;
}
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=(int)nodes.size()-1;i>=0;i--)
{
if(cnt%10==0) printf(" ");
printf(" (%d,%d)",nodes[i].r,nodes[i].c);
if(++cnt%10==0) printf("\n");
}
if(cnt%10!=0) printf("\n");
}
void solve()
{
queue<Node> q;
Node u(r1,c1,dir);
memset(d,-1,sizeof(d));
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(have_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_case()){
solve();
}
return 0;
}