HDU–1195–bfs–Open the Lock

/*    Name: HDU--1195--Open the Lock    Author: shen_渊    Date: 17/04/17 08:54    Description: bfs，用四维数组标记状态，每位数字可以做三种操作 +1，-1，交换                可以不用优先队列，题意决定，优先队列更费时间*/#include<iostream>#include<queue>#include<cstring>using namespace std;struct node{    int steps;    string s;    node():steps(){    };    bool operator <(const node &a)const{        return steps>a.steps;    }};int bfs();][][][];string str1,str2;int main(){    ios::sync_with_stdio(false);//    freopen("in.txt","r",stdin);    int n;cin>>n;    while(n--){        memset(vis,,sizeof(vis));        cin>>str1>>str2;        if(str1 == str2)cout<<"0\n";        else cout<<bfs()<<endl;    }    ;}int bfs(){    priority_queue<node> q;    node p;    p.s = str1;    q.push(p);    vis[p.s[]-]-]-]-;    while(!q.empty()){        node a,temp;        temp = q.top();q.pop();        if(temp.s == str2)return temp.steps;        ; i<; ++i) {            //+1            a.s = temp.s;            ';            ;            ]-]-]-]-']){                a.steps = temp.steps + ;                q.push(a);                vis[a.s[]-]-]-]-;            }            //-1            a.s = temp.s;            ';            ;            ]-]-]-]-']){                a.steps = temp.steps + ;                q.push(a);                vis[a.s[]-]-]-]-;            }            //交换            ){                a.s = temp.s;                a.s[i] = temp.s[i+];                a.s[i+] = temp.s[i];                ]-]-]-]-']){                a.steps = temp.steps + ;                q.push(a);                vis[a.s[]-]-]-]-;                }            }        }    }    ;}