ZJU 1005 Jugs

分析：简单的BFS一次，用二维矩阵来记住已搜索或正在搜索点。

 

#include <iostream>
#include <queue>
#include <vector>
using namespace std;

int memory[1001][1001],n,fullA,fullB;
struct Jugs
{
    int a,b;
    vector<int> v;
}success_result;

void Display(Jugs t)
{
    vector<int>::iterator begin=t.v.begin(),end=t.v.end();
    for(;begin!=end;++begin)
    {
        switch(*begin)
        {
            case 1: cout<<"fill A"<<endl; break;
            case 2: cout<<"fill B"<<endl; break;
            case 3: cout<<"empty A"<<endl; break;
            case 4: cout<<"empty B"<<endl; break;
            case 5: cout<<"pour A B"<<endl; break;
            case 6: cout<<"pour B A"<<endl; break;
        }
    }
    cout<<"success"<<endl;
}
int main()
{
    queue<Jugs> que;
    while(cin>>fullA>>fullB>>n)
    {
        memset(memory,0,1001*1001*sizeof(int));
        Jugs t,temp;
        t.a = 0; t.b = 0;
        que.push(t);
        memory[0][0] = 63;
        bool found = false;
        while(!que.empty())
        {
            t = que.front();
            
            bool result = false;
            if(!(memory[fullA][t.b]&1) && t.a!=fullA)
            {
                memory[fullA][t.b] |= 1;
                temp = t;
                temp.v.push_back(1);
                temp.a = fullA;
                //if(temp.a==n || temp.b==n)
                if(temp.b==n)
                { success_result = temp; break; }
                que.push(temp);
            }
            if(!(memory[t.a][fullB]&2) && t.b!=fullB)
            {
                memory[t.a][fullB] |=2;
                temp = t;
                temp.v.push_back(2);
                temp.b = fullB;
                //if(temp.a==n || temp.b==n)
                if(temp.b==n)
                { success_result = temp; break; }
                que.push(temp);
            }
            if(!(memory[0][t.b]&4) && t.a!=0)
            {
                memory[0][t.b] |= 4;
                temp = t;
                temp.v.push_back(3);
                temp.a = 0;
                //if(temp.a==n || temp.b==n)
                if(temp.b==n)
                { success_result = temp; break; }
                que.push(temp);
            }
            if(!(memory[t.a][0]&8) && t.b!=0)
            {
                memory[t.a][0] |= 8;
                temp = t;
                temp.v.push_back(4);
                temp.b = 0;
                //if(temp.a==n || temp.b==n)
                if(temp.b==n)
                { success_result = temp; break; }
                que.push(temp);
            }
            if(t.b!=fullB && t.a!=0)
            {
                temp = t;
                temp.v.push_back(5);
                if(fullB-t.b>=t.a && !(memory[0][t.b+t.a]&16))
                {
                    memory[0][t.b+t.a] |= 16;
                    temp.a = 0;
                    temp.b = t.b+t.a;
                    //if(temp.a==n || temp.b==n)
                    if(temp.b==n)
                    { success_result = temp; break; }
                    que.push(temp);
                }
                else if(fullB-t.b<t.a && !(memory[t.a-fullB+t.b][fullB]&16))
                {
                    memory[t.a-fullB+t.b][fullB] |= 16;
                    temp.a = t.a-fullB+t.b;
                    temp.b = fullB;
                    //if(temp.a==n || temp.b==n)
                    if(temp.b==n)
                    { success_result = temp; break; }
                    que.push(temp);
                }
            }
            if(t.a!=fullA && t.b!=0)
            {
                temp = t;
                temp.v.push_back(6);
                if(fullA-t.a>=t.b && !(memory[t.a+t.b][0]&32))
                {
                    memory[t.a+t.b][0] |= 32;
                    temp.b = 0;
                    temp.a = t.a+t.b;
                    //if(temp.a==n || temp.b==n)
                    if(temp.b==n)
                    { success_result = temp; break; }
                    que.push(temp);
                }
                else if(fullA-t.a<t.b && !(memory[fullA][t.b-fullA+t.a]&32))
                {
                    memory[fullA][t.b-fullA+t.a] |= 32;
                    temp.a = fullA;
                    temp.b = t.b-fullA+t.a;
                    //if(temp.a==n || temp.b==n)
                    if(temp.b==n)
                    { success_result = temp; break; }
                    que.push(temp);
                }
            }
            que.pop();
        }
        Display(success_result);
        while(!que.empty())
            que.pop();
    }
    return 0;
}