题目链接：http://acm.hdu.edu.cn/showproblem.php?pid=1495
7 4 3 4 1 3 0 0 0
NO 3
代码如下：
#include <cstdio>
#include <cstring>
#include<iostream>
#include<algorithm>
#include<queue>
using namespace std;
#define MAXN 117
bool vis[MAXN][MAXN];
int s, n, m;
struct node
{
int x,y,all; //x,y,all分别表示n,m,s杯中可乐现有的体积
int t; //步数
};
void BFS()
{
queue<node> Q;
memset(vis,false,sizeof(vis));
node p,q;
p.x = 0,p.y = 0,p.t = 0,p.all = s;
Q.push(p);
vis[p.x][p.y] = true;
while(!Q.empty())
{
p = Q.front();
Q.pop();
if(p.x == p.all && p.x == s/2)
{
printf("%d\n",p.t);
return;
}
if(p.all+p.x > n) //s倒n
{
q.x = n,q.y = p.y,q.all = p.all+p.x-n,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
else
{
q.x = p.all+p.x,q.y = p.y,q.all = 0,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
if(p.all+p.y > m) //s倒m
{
q.x = p.x, q.y = m, q.all = p.all+p.y-m,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
else
{
q.x = p.x,q.y = p.all+p.y,q.all = 0,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
if(p.x+p.y > m) //n倒m
{
q.x = p.x+p.y-m,q.y = m,q.all = p.all,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
else
{
q.x = 0,q.y = p.x+p.y,q.all = p.all,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
if(p.x+p.y > n)
{
q.y = p.y+p.x-n,q.x = n,q.all = p.all,q.t = p.t+1;//m倒n
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
else
{
q.x = p.x+p.y,q.y = 0,q.all = p.all,q.t = p.t+1;
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
q.all = p.all+p.x,q.x = 0,q.y = p.y,q.t = p.t+1; //n倒s
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
q.all = p.all+p.y,q.x = p.x,q.y = 0,q.t = p.t+1; //m倒s
if(!vis[q.x][q.y])
{
Q.push(q);
vis[q.x][q.y] = true;
}
}
printf("NO\n");
}
int main()
{
while(~scanf("%d%d%d",&s,&n,&m))
{
if(s==0 && n==0 && m==0)
break;
if(s%2)
{
printf("NO\n");
continue;
}
if(n < m)
{
int t = n;
n = m;
m = t;
}
BFS();
}
return 0;
}
原文地址：http://blog.csdn.net/u012860063/article/details/39202657
