Bzoj 1054 Mobile Toys

Title Link: http://www.lydsy.com/JudgeOnline/problem.php?id=1054

Exercises

Blind Basic Search is no hope, or normal BFS more reliable
See the 4*4 of the lattice of each row together is a 01 string, can be used similar to the state compression of the idea to solve, convert it into a decimal number, mainly to determine whether it has reached the ideal state

Queue storage State, in the BFS when the team first, for each piece of the four kinds of movement to create a new state, and then queue processing can be

(A little confused about why the "hash" was used to name this state compression ...) ）

1#include <cstdio>2#include <cstring>3 intst,en,_x[]={0,0,0,-1,1},_y[]={0,1,-1,0,0};4 BOOLvis[65536];5 structnode6 {7     BOOLstatus[5][5];8     intDEP;9}q[65536];TenInlineintHashBOOLa[5][5]) One { A     intk=1, ans=0; -      for(intI=1; i<=4; i++) -     { the          for(intj=1; j<=4; j + +) -         { -ans+=a[i][j]*K; -k<<=1; +         } -     } +     returnans; A } at voidInit () - { -     Chartemp[5]; -     BOOLtemp2[5][5]; -      for(intI=1; i<=4; i++) -     { inscanf"%s", temp+1); -          for(intj=1; j<=4; j + +) to         { +q[1].status[i][j]=temp[j]-'0'; -         } the     } *      for(intI=1; i<=4; i++) $     {Panax Notoginsengscanf"%s", temp+1); -          for(intj=1; j<=4; j + +) the         { +temp2[i][j]=temp[j]-'0'; A         } the     } +St=hash (q[1].status); -en=hash (TEMP2); $ } $ voidBFS () - { -vis[st]=true; the     intHead=1, tail=2; -      while(head<tail)Wuyi     { the          for(intI=1; i<=4; i++) -         { Wu              for(intj=1; j<=4; j + +) -             { About                 if(Q[head].status[i][j]) $                 { -                      for(intk=1; k<=4; k++) -                     { -                         intx=i+_x[k],y=j+_y[k]; A                         if(q[head].status[x][y]| |! X| |! y| | X>4|| Y>4)Continue; +q[head].status[i][j]=false; theq[head].status[x][y]=true; -                         inthash_of_status=hash (q[head].status); $                         if(!Vis[hash_of_status]) the                         { the                             if(hash_of_status==en) the                             { theprintf"%d", q[head].dep+1); -                                 return; in                             } thememcpy (Q[tail].status,q[head].status,sizeof(Q[tail].status)); theq[tail++].dep=q[head].dep+1; Aboutvis[hash_of_status]=true; the                         } theq[head].status[i][j]=true; theq[head].status[x][y]=false; +                     } -                 } the             }Bayi         } thehead++; the     } - } - intMain () the { the init (); the     if(st==en) the     { -printf"0\n"); the         return 0; the     } the BFS ();94     return 0; the}

Bzoj 1054 Mobile Toys