UVA 11624 fire!

Data:

3
4 4
####
#JF #
#.. #
#.. #
3 3
FFF
Fjf
FFF
3 3
...
. J.
...

Well, the third data card for half a day ....

Two BFS pre-processing the earliest fire time of each point.

/************************************************author:p k29created time:2015/8/19 19:26:13File name:4.c pp*************************************************/#include<iostream>#include<cstring>#include<cstdlib>#include<stdio.h>#include<algorithm>#include<vector>#include<queue>#include<Set>#include<map>#include<string>#include<math.h>#include<stdlib.h>#include<iomanip>#include<list>#include<deque>#include<stack>#defineull unsigned long Long#definell Long Long#defineMoD 90001#defineINF 0x3f3f3f3f#defineMAXN 10000+10#defineCLE (a) memset (A,0,sizeof (a))Constull inf = 1LL << A;Const Doubleeps=1e-5;using namespacestd;structnode{intx,y,dist;};BOOLcmpintAintb) {    returnA>b;}intdir[4][2]={1,0,0,1,0,-1,-1,0};Charmp[1100][1100];intvis[1100][1100],val[1100][1100];intN,m,sx,sy,fx,fy;queue<node>p;voidBFS1 () {CLE (VIS);    Node u,v;  while(!P.empty ()) {u=P.front (), P.pop ();  for(intI=0;i<4; i++){            intnx=u.x+dir[i][0]; intny=u.y+dir[i][1]; if(!vis[nx][ny]&&nx<=n&&ny>=1&&nx>=1&&ny<=m&&mp[nx][ny]=='.') {v.x=nx,v.y=ny,v.dist=u.dist+1; Vis[nx][ny]=1; Val[nx][ny]=v.dist;            P.push (v); }}}}queue<node>Q;voidbfs2 () {intmark=0;    CLE (VIS);  while(!q.empty ()) Q.pop ();    Node u,v; u.x=sx,u.y=sy,u.dist=0;    Q.push (U); VIS[U.X][U.Y]=1;  while(!Q.empty ()) {u=Q.front (), Q.pop (); if(u.x==n| | u.x==1|| u.y==1|| u.y==m) {Mark=1;p rintf ("%d\n", u.dist+1); Break; }         for(intI=0;i<4; i++){            intnx=u.x+dir[i][0]; intny=u.y+dir[i][1]; if(vis[nx][ny]==0&&nx<=n&&ny>=1&&nx>=1&&ny<=m&&mp[nx][ny]=='.') {v.dist=u.dist+1; if(v.dist<Val[nx][ny]) {v.x=nx,v.y=NY;                    Q.push (v); Vis[nx][ny]=1; }            }        }    }    if(!mark) printf ("impossible\n");}intMain () {#ifndef Online_judge freopen ("In.txt","R", stdin); #endif    //freopen ("OUT.txt", "w", stdout);    intT; CIN>>T;  while(t--) {cin>>n>>m;        CLE (MP); memset (Val,inf,sizeofval);  for(intI=1; i<=n;i++)             for(intj=1; j<=m;j++) {cin>>Mp[i][j]; if(mp[i][j]=='J') {SX=i,sy=J; }                if(mp[i][j]=='F') {node o;o.x=i,o.y=j,o.dist=0;                P.push (o);        }} BFS1 ();    BFS2 (); }    return 0;}

UVA 11624 fire!