HDU 1495 非常可乐

非常可乐

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others) Total Submission(s): 3654    Accepted Submission(s): 1522

Problem Description

大家一定觉的运动以后喝可乐是一件很惬意的事情，但是seeyou却不这么认为。因为每次当seeyou买了可乐以后，阿牛就要求和seeyou一起分享这一瓶可乐，而且一定要喝的和seeyou一样多。但seeyou的手中只有两个杯子，它们的容量分别是N 毫升和M 毫升 可乐的体积为S （S<101）毫升　(正好装满一瓶) ，它们三个之间可以相互倒可乐 (都是没有刻度的，且 S==N+M，101＞S＞0，N＞0，M＞0) 。聪明的ACMER你们说他们能平分吗？如果能请输出倒可乐的最少的次数，如果不能输出"NO"。

 

Input

三个整数 : S 可乐的体积 , N 和 M是两个杯子的容量，以"0 0 0"结束。

 

Output

如果能平分的话请输出最少要倒的次数，否则输出"NO"。

 

Sample Input

7 4 3

4 1 3

0 0 0

 

Sample Output

NO

3

 

Author

seeyou

 

Source

“2006校园文化活动月”之“校庆杯”大学生程序设计竞赛暨杭州电子科技大学第四届大学生程序设计竞赛

 

Recommend

LL

 

思路：BFS，需要考虑的情况比较多，相比之下我的代码比较水，看类长路漫漫啊

 

代码：

#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
using namespace std;
int hash[110][110][110];
int s,n,m;
struct Node
{
    int s,n,m;
    int step;
};
int BFS()
{
    queue <Node> q;
    Node top;top.s = s;top.n = 0;top.m = 0;top.step = 0;
    q.push(top);
    while(!q.empty())
    {
        Node temp = q.front();q.pop();
        if(temp.s == s / 2 && (temp.n == s / 2 || temp.m == s / 2))
                  return temp.step;
        if(temp.n == s / 2 && (temp.s == s / 2 || temp.m == s / 2))
                  return temp.step;
        if(temp.m == s / 2 && (temp.s == s / 2 || temp.n == s / 2))
                  return temp.step;
        //printf("%d %d %d have %d ",temp.s,temp.n,temp.m,temp.step);
        if(temp.s != 0)
        {
            if(temp.n != n)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                //printf("%d %d %d have %d ",temp.s,temp.n,temp.m,temp.step);
                if(y + x <= n)
                {
                    y = x + y;
                    x = 0;
                    z = z;
                    step = step + 1;
                }
                else
                {
                    x = x - (n - y);
                    y = n;
                    z = z;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                  Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                  q.push(xin);
                  //printf("%d %d %d have %d ",x,y,z,step);
                  hash[x][y][z] = 1;
                }
            }
            if(temp.m != m)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                if(z + x <= m)
                {
                    z = x + z;
                    x = 0;
                    y = y;
                    step = step + 1;
                }
                else
                {
                    x = x - (m - z);
                    z = m;
                    y = y;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                  Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                  q.push(xin);
                  //printf("%d %d %d have %d ",x,y,z,step);
                  hash[x][y][z] = 1;
                }
             }
         }
         if(temp.n != 0)
         {
            if(temp.s != s)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                if(y + x <= s)
                {
                    x = x + y;
                    y = 0;
                    z = z;
                    step = step + 1;
                }
                else
                {
                    y = y - (s - x);
                    x = s;
                    z = z;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                  Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                  q.push(xin);
                  //printf("%d %d %d have %d ",x,y,z,step);
                  hash[x][y][z] = 1;
                }
            }
            if(temp.m != m)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                if(z + y <= m)
                {
                    z = y + z;
                    y = 0;
                    x = x;
                    step = step + 1;
                }
                else
                {
                    y = y - (m - z);
                    z = m;
                    x = x;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                  Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                  q.push(xin);
                  ///printf("%d %d %d have %d ",x,y,z,step);
                  hash[x][y][z] = 1;
                }
             }
         }
         if(temp.m != 0)
        {
            if(temp.n != n)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                if(y + z <= n)
                {
                    y = z + y;
                    z = 0;
                    x = x;
                    step = step + 1;
                }
                else
                {
                    z = z - (n - y);
                    y = n;
                    x = x;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                   Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                   q.push(xin);
                   //printf("%d %d %d have %d ",x,y,z,step);
                   hash[x][y][z]  = 1;
                }
            }
            if(temp.s != s)
            {
                int x = temp.s;int y = temp.n;int z = temp.m;int step = temp.step;
                if(z + x <= s)
                {
                    x = x + z;
                    z = 0;
                    y = y;
                    step = step + 1;
                }
                else
                {
                    z = z - (s - x);
                    x = s;
                    y = y;
                    step = step + 1;
                }
                if(hash[x][y][z] == 0)
                {
                  Node xin;xin.s = x;xin.n = y;xin.m = z;xin.step = step;
                  q.push(xin);
                  //printf("%d %d %d have %d ",x,y,z,step);
                  hash[x][y][z] = 1;
                }
             }
        }
    }
    return -1;
}            
int main()
{
    while(scanf("%d%d%d",&s,&n,&m),s != 0 && n != 0 && m != 0)
    {
        memset(hash,0,sizeof(hash));
        hash[s][n][m] = 1;
        int sss = BFS();
        if(s % 2 == 1)
           sss = -1;
        if(sss == -1)
            printf("NO ");
        else
            printf("%d ",sss);
    }
    return 0;
}