poj3278广搜

#include<stdio.h> 
struct node
{
    int step;
    int x;
}s,temp; 
struct node que[100006];
int n,k;
int vis[100006];
int bfs(int step,int x)
{
    int f=0,r=0;
    s.step=step;
    s.x=x;
    que[r]=s;
    vis[x]=1;
    r++;
    while(f<r)
    {
        node p=que[f]; f++;
        if(p.x==k)  
            return p.step;
        if(p.x*2<100001 && vis[p.x*2]!=1)  //注意p.x不是x***
        {
            temp.step=p.step+1; 
            temp.x=p.x*2;
            que[r]=temp;
            vis[p.x*2]=1;
            r++;
        }
        if(p.x+1<100001 && vis[p.x+1]!=1)
        {
            temp.step=p.step+1;
            temp.x=p.x+1;
            que[r]=temp;
            vis[p.x+1]=1;
            r++;
        }
        if(p.x-1>=0 && vis[p.x-1]!=1)
        {
            temp.step=p.step+1;
            temp.x=p.x-1;
            que[r]=temp;
            vis[p.x-1]=1;
            r++;
        }
    }
    return 0;
}
int main()
{
    scanf("%d%d",&n,&k);
    printf("%d",bfs(0,n));
    return 0;
}

/*
5 17
4
*/