poj3278基本广搜

#include<iostream>#include<algorithm>#include<queue>#define MAX 100001using namespace std;int N,K;bool map[MAX];struct node{int x;int steps;};int bfs(){queue<node> que;node pre;pre.x=N;pre.steps=0;map[pre.x]=1;que.push(pre);while(!que.empty()){pre=que.front();que.pop();if(pre.x==K){return pre.steps;}node a[3];a[0].x=pre.x+1;a[1].x=pre.x-1;a[2].x=pre.x*2;a[0].steps=a[1].steps=a[2].steps=pre.steps+1;for(int i=0;i<3;i++){if(a[i].x>=0&&a[i].x<MAX&&map[a[i].x]==0){map[a[i].x]=1;que.push(a[i]);}}}}int main(){while(scanf("%d%d",&N,&K)==2){printf("%d/n",bfs());memset(map,false,sizeof(map));}return 0;}