//#include "stdafx.h"


#include <stdio.h>
struct Node
{
	int num;
	struct Node *pre;
}mNodeList[200002];


int N,K;
int index=1,count=1,temp,steps=0;

void BFS()
{
	int map[200002]={0};
	struct Node firstNode,mNodeLeft,mNodeRight,mNodeDouble;
	firstNode.num = N;
	firstNode.pre = NULL;
	mNodeList[1] = firstNode;
	map[N] = -1;
	do
	{
		mNodeLeft.num = mNodeList[index].num-1;
		mNodeLeft.pre = &mNodeList[index];

		mNodeRight.num = mNodeList[index].num+1;
		mNodeRight.pre = &mNodeList[index];

		mNodeDouble.num = mNodeList[index].num*2;
		mNodeDouble.pre = &mNodeList[index];
		if(mNodeDouble.num <=200000 && map[mNodeDouble.num] != -1)
		{
			mNodeList[++count] = mNodeDouble;
			map[mNodeDouble.num] = -1;
		}

		if(mNodeRight.num <=100000 && map[mNodeRight.num] != -1)
		{
			mNodeList[++count] = mNodeRight;
			map[mNodeRight.num] = -1;
		}

		if(mNodeLeft.num>=0 && map[mNodeLeft.num] != -1)
		{
		   mNodeList[++count] = mNodeLeft;
		   map[mNodeLeft.num] = -1;
		}

		index++;
	}while(mNodeLeft.num!=K&&mNodeRight.num!=K&&mNodeDouble.num!=K);

	if(mNodeLeft.num == K)
	{
		temp = count-2;
	}else if(mNodeRight.num == K)
	{
		temp = count-1;
	}else
		temp = count;
	struct Node tempNode;
	tempNode = mNodeList[temp];
	while(tempNode.pre != NULL)
	{
		tempNode = *tempNode.pre;
		steps++;
	}

    if(N>=K)
		printf("%d\n",N-K);
	else
	    printf("%d\n",steps);
}

int main()
{
	while(scanf("%d%d", &N, &K) != EOF)
	{
		index=1;count=1;temp=0;steps=0;
		BFS();
	}
	return 0;
}

• Re:本地各种测试case各种过，提上去就是WA....求助！！ (1737) bajieguagua 2015-10-28 20:51:53
• Re:本地各种测试case各种过，提上去就是WA....求助！！ (1737) 20152430125 2017-05-20 16:31:33