AtCoder Beginner Contest 132 E - Hopscotch Addict

bfs

位置+状态

just need to calculate min value(only it is useful), so O(1*x)

挺有趣的一道题。。。

 #include <cstdio>
 #include <cstdlib>
 #include <cmath>
 #include <cstring>
 #include <string>
 #include <algorithm>
 #include <iostream>
 using namespace std;
 #define ll long long

 const int maxn=1e6+;

 struct node
 {
     int d;
     node *to;
 }*e[maxn];

 int qx[maxn*],qy[maxn*],qz[maxn*];

 int f[maxn][];

 int main()
 {
     node *p;
     int n,m,x,y,z,xx,yy,zz,head,tail,s,t;
     scanf("%d%d",&n,&m);
     while (m--)
     {
         scanf("%d%d",&x,&y);
         p=new node();
         p->d=y;
         p->to=e[x];
         e[x]=p;
     }

     scanf("%d%d",&s,&t);
     qx[]=s,qy[]=,qz[]=;
     head=,tail=;
     while (head<tail)
     {
         head++;
         x=qx[head];
         y=qy[head];
         z=qz[head];

         p=e[x];
         while (p)
         {
             xx=p->d;
             yy=(y+)%;
             zz=z+;
             if (!f[xx][yy])
             {
                 if (xx==t && yy==)
                 {
                     printf("%d",(zz-)/);
                     return ;
                 }
                 tail++;
                 qx[tail]=xx;
                 qy[tail]=yy;
                 qz[tail]=zz;
                 f[xx][yy]=zz;
             }
             p=p->to;
         }
     }
     printf("-1");
     return ;
 }