catch that cow

http://poj.org/problem?id=3278

Source Code

Problem: 3278  User: SDUT_NULL 
Memory: 1068K  Time: 63MS 
Language: G++  Result: Accepted 

Source Code 
#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstring>
#include<queue>
bool s[200010];
using namespace std;
struct node
{
    int num;
    int count;
} st,st1;
void bfs(int n,int k)
{
    queue<node>q;
    if(n==k) {printf("0
");return;}
    st.num=n;
    st.count=0;
    s[n]=true;
    q.push(st);
    while(!q.empty())
    {
        st1=q.front();
        q.pop();
        if(st1.num==k)break;
        else
        {
            if(st1.num-1>=0&&st1.num-1<=100010&&!s[st1.num-1])
            {
                st.num=st1.num-1;
                st.count=st1.count+1;
                s[st1.num-1]=true;
                q.push(st);
            }
            if(st1.num+1>=0&&st1.num+1<=100010&&!s[st1.num+1])
            {
                st.num=st1.num+1;
                st.count=st1.count+1;
                s[st1.num+1]=true;
                q.push(st);
            }
            if(st1.num*2>=0&&st1.num*2<=100010&&!s[st1.num*2])
            {
                st.num=st1.num*2;
                st.count=st1.count+1;
                s[st1.num*2]=true;
                q.push(st);
            }
        }
    }
    printf("%d
",st1.count);
}
int main()
{
    int n,k;
    while(scanf("%d%d",&n,&k)!=EOF)
    {
        memset(s,false,sizeof(s));
        bfs(n,k);
    }
    return 0;
}