POJ 2243:knight Moves (BFS)

It can be understood that the horse in chess goes the "Day" glyph, the shortest number of steps required from the first position to the second position, and a simple BFS

Each step must be judged whether it reaches the target point at a time.

Because BFS write not much, has been using Dfs thinking understanding, recursive write always overflow, timeout ~ ~

#include"Cstdio"#include"iostream"#include"CString"#include"Queue"using namespacestd;intdx[8]={-1,1,-2,2,-2,2,-1,1};intdy[8]={-2,-2,-1,-1,1,1,2,2};intvis[Ten][Ten];structpoint{intx; inty; intLevel ;};BOOLjudge (point P) {if(vis[p.x][p.y]| | P.x>8|| p.x<=0|| P.y>8|| p.y<=0)return false; return true;}intMain () {Chara1,b; intans;    Point P1,p2;  while(SCANF ("%c%d%c%d", &a1,&p1.y,&b,&p2.y)! =EOF)        {GetChar (); memset (Vis,0,sizeof(VIS)); Ans=0; p1.x=a1-'a'+1;p 2.x=b-'a'+1; P1.level=0; Queue<point>Q;        Q.push (p1); VIS[P1.X][P1.Y]=1;        Point A;  while(!Q.empty ()) {a=Q.front ();            Q.pop (); if(A.X==P2.X&AMP;&AMP;A.Y==P2.Y) {ans=a.level; Break;}  for(intI=0;i<8; i++) {Point temp; Temp.x=a.x+Dx[i]; TEMP.Y=a.y+Dy[i]; Temp.level=a.level+1; if(Judge (temp)) {VIS[TEMP.X][TEMP.Y]=1;                Q.push (temp); }}} printf ("To get from%c%d to%c%d takes%d Knight moves.\n", A1,p1.y,b,p2.y,ans); }    return 0;}

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POJ 2243:knight Moves (BFS)