#include<bits/stdc++.h>
using namespace std;
int Vis[205][205];
const int inf=0x3f3f3f3f;
int minhh(int x,int y)
{
if(x<=y)return x;
else return y;
}
struct glass
{
int s,n,m,steps;
}gg;
int main()
{
int S,N,M,s,n,m;
queue<struct glass>q;
while(scanf("%d %d %d",&S,&N,&M),S)
{
gg.s=S;gg.n=0;gg.m=0;gg.steps=0;
memset(Vis,0,sizeof(Vis));
q.push(gg);
while(!q.empty())
{
gg=q.front();
q.pop();//读取后不要忘记把元素移出队列
if((gg.s==gg.m&&gg.n==0)||(gg.s==gg.n&&gg.m==0)||(gg.n==gg.m&&gg.s==0)){S=-1;break;}
if(Vis[gg.s][gg.n]==0)
{
Vis[gg.s][gg.n]=1;//要注意区分杯子的容量和操作后的实际含量
s=gg.s;n=gg.n;m=gg.m;
if(gg.s+gg.m<=M){gg.m+=gg.s;gg.s=0;}
else{gg.s-=M-gg.m;gg.m=M;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//s->m
if(gg.s+gg.n<=N){gg.n+=gg.s;gg.s=0;}
else{gg.s-=N-gg.n;gg.n=N;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//s->n
if(gg.s+gg.n<=S){gg.s+=gg.n;gg.n=0;}
else{gg.n-=S-gg.s;gg.s=S;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//n->s
if(gg.m+gg.n<=M){gg.m+=gg.n;gg.n=0;}
else{gg.n-=M-gg.m;gg.m=M;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//n->m
if(gg.m+gg.s<=S){gg.s+=gg.m;gg.m=0;}
else{gg.m-=S-gg.s;gg.s=S;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//m->s
if(gg.m+gg.n<=N){gg.n+=gg.m;gg.m=0;}
else{gg.m-=N-gg.n;gg.n=N;}
gg.steps++;q.push(gg);gg.steps--;//记录是第几层
gg.s=s;gg.n=n;gg.m=m;//m->n
}
}
if(S==-1)printf("%d\n",gg.steps);
else printf("NO\n");
while(!q.empty())//清空队列
{
q.pop();
}
}
return 0;
}
总结
1.队列的六种基本操作
2.队列使用后不要忘记清空队列（特别是多组输入数据，大多情况需要初始化）
3.需要时，读取元素后不要忘记把它清出队列，这两个操作是分开的
4.本题需要注意区分杯子的实际含量和容量
