BFS + 剪枝 之 hdu 5012 Dice

/*
BFS 遍历所有状态，当寻找到要转到的状态，输出BFS的层数，即答案，否则输出 -1；
注意：
剪枝： 当BFS到某一种状态时，若此状态已在前面所寻找的状态中出现过，则不用再继续从此状态BFS了，因为此状态所能寻找的状态已经在之前都处理过了。
*/

#include <iostream>
#include <cstdlib>
#include <cstdio>
#include <queue>
#include <vector>
#include <map>
using namespace std;
struct myNode {
int Top, Bottom, Left, Right, Front, Back;
};
typedef pair<myNode, int> P;

myNode node[2];
vector<myNode> vec;

void myDeal(int myCase, myNode myNd, myNode &t_Nd) {
// top face, bottom face, left face, right face, front face and back face
switch (myCase) {
case 1: {
t_Nd.Top = myNd.Right;
t_Nd.Bottom = myNd.Left;
t_Nd.Left = myNd.Top;
t_Nd.Right = myNd.Bottom;
t_Nd.Front = myNd.Front;
t_Nd.Back = myNd.Back;
return;
}
case 2: {
t_Nd.Top = myNd.Left;
t_Nd.Bottom = myNd.Right;
t_Nd.Left = myNd.Bottom;
t_Nd.Right = myNd.Top;
t_Nd.Front = myNd.Front;
t_Nd.Back = myNd.Back;
return;
}
case 3: {
t_Nd.Top = myNd.Back;
t_Nd.Bottom = myNd.Front;
t_Nd.Front = myNd.Top;
t_Nd.Back = myNd.Bottom;
t_Nd.Left = myNd.Left;
t_Nd.Right = myNd.Right;
return;
}
case 4: {
t_Nd.Top = myNd.Front;
t_Nd.Bottom = myNd.Back;
t_Nd.Front = myNd.Bottom;
t_Nd.Back = myNd.Top;
t_Nd.Left = myNd.Left;
t_Nd.Right = myNd.Right;
return;
}
default:
system("pause");
return;
}
}

bool myJudge(const myNode n1, const myNode n2) {
if ((n1.Top == n2.Top) && (n1.Bottom == n2.Bottom) && (n1.Front == n2.Front) &&
(n1.Back == n2.Back) && (n1.Left == n2.Left) && (n1.Right == n2.Right)) {
return true;
}
return false;
}

bool Judge(myNode nd) {
for (int i = 0; i < vec.size(); ++i) {
if (myJudge(vec[i], nd)) {
return true;
}
}
return false;
}

void Solve() {
queue<P> que;
que.push(P(node[0], 0));
while (!que.empty()) {
P p1 = que.front();
if (Judge(p1.first)){
//cout << "Yes" << endl;
que.pop();
continue;
}
vec.push_back(p1.first);
que.pop();
if (myJudge(p1.first, node[1])) {
printf("%d\n", p1.second);
return;
}
myNode t_Nd;
for (int i = 1; i <= 4; ++i) {
myDeal(i, p1.first, t_Nd);
//cout << t_Nd.Top << " " << t_Nd.Bottom << " " << t_Nd.Left << " " << t_Nd.Right << " " << t_Nd.Front << " " << t_Nd.Back << endl;
que.push(P(t_Nd, p1.second + 1));
}
}
printf("-1\n");
}

int main() {
//freopen("input.txt", "r", stdin);
int n;
while (~scanf("%d %d %d %d %d %d", &node[0].Top, &node[0].Bottom, &node[0].Left, &node[0].Right, &node[0].Front, &node[0].Back)) {
scanf("%d %d %d %d %d %d", &node[1].Top, &node[1].Bottom, &node[1].Left, &node[1].Right, &node[1].Front, &node[1].Back);
Solve();
if (!vec.empty()) vec.clear();
}
return 0;
}