hdu 1495 非常可乐

#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
using namespace std;
struct sta {
    int ar[3];
    sta(){}
    sta(int a,int b,int c) {
        ar[0] = a;
        ar[1] = b;
        ar[2] = c;
    }
};
typedef pair<sta,int> pa;
int ar[3];
int order[6][3] = {0,1,2,0,2,1,1,0,2,1,2,0,2,0,1,2,1,0};
bool vis[1000001];
bool check(const sta &temp) {
    int d = temp.ar[0] * 10000 + temp.ar[1] * 100 + temp.ar[2];
    bool e = vis[d];
    vis[d] = true;
    return e;
}
sta change(const sta &temp,int a,int b,int c) {
    sta temp1;
    if(temp.ar[a] > ar[b] - temp.ar[b]) {
        temp1.ar[a] = temp.ar[a] - ar[b] + temp.ar[b];
        temp1.ar[b] = ar[b];
    }
    else {
        temp1.ar[a] = 0;
        temp1.ar[b] = temp.ar[b] + temp.ar[a];
    }
    temp1.ar[c] = temp.ar[c];
    return temp1;
}
int bfs() {
    if(ar[0] % 2) return 0;
    queue<pa> q;
    q.push(pa(sta(ar[0],0,0),0));
    check(sta(ar[0],0,0));
    while(!q.empty()) {
        sta temp = q.front().first,temp1;
        int times = q.front().second;
        q.pop();
        for(int i = 0;i < 6;i ++) {
            temp1 = change(temp,order[i][0],order[i][1],order[i][2]);
            if(temp1.ar[0] == ar[0] / 2 || temp1.ar[1] == ar[0] / 2 || temp1.ar[2] == ar[0] / 2) return times + 1 + (temp1.ar[0] && temp1.ar[1] && temp1.ar[2]);
            if(!check(temp1)) q.push(pa(temp1,times + 1));
        }
    }
    return 0;
}
int main() {
    while(scanf("%d%d%d",&ar[0],&ar[1],&ar[2]) && ar[0] && ar[1] && ar[2]) {
        memset(vis,false,sizeof(vis));
        int ans = bfs();
        if(ans)printf("%d\n",ans);
        else printf("NO\n");
    }
}