HDU5012-Dice (BFS)

Question Link

Question: Here are two sides. If you can rotate the two sides to make them equal one by one (given in the title of the rotation rule), find the minimum number of steps. If not, output-1.

Idea: Use BFs to calculate the minimum number of steps.

Code:

#include <iostream>#include <cstdio>#include <cstring>#include <queue>#include <algorithm>using namespace std;const int MAXN = 6;struct node{    node() {        memset(arr, 0, sizeof(arr));        d = 0;     }    int arr[MAXN], d;}s, e;int vis[MAXN * 200000];int change(node a) {    int num = 0;    for (int i = 0; i < MAXN; i++) {        num = num * 10 + a.arr[i];     }    return num;}bool judge(node a, node b) {    for (int i = 0; i < MAXN; i++)        if (a.arr[i] != b.arr[i])            return false;    return true;}node turn(node a, int i) {    node c;    if (i == 1) {        c.arr[0] = a.arr[3];        c.arr[1] = a.arr[2];        c.arr[2] = a.arr[0];        c.arr[3] = a.arr[1];        c.arr[4] = a.arr[4];        c.arr[5] = a.arr[5];     }    if (i == 2) {        c.arr[0] = a.arr[2];        c.arr[1] = a.arr[3];        c.arr[2] = a.arr[1];        c.arr[3] = a.arr[0];         c.arr[4] = a.arr[4];        c.arr[5] = a.arr[5];     }    if (i == 3) {        c.arr[0] = a.arr[5];        c.arr[1] = a.arr[4];        c.arr[2] = a.arr[2];        c.arr[3] = a.arr[3];         c.arr[4] = a.arr[0];        c.arr[5] = a.arr[1];     }    if (i == 4) {        c.arr[0] = a.arr[4];        c.arr[1] = a.arr[5];        c.arr[2] = a.arr[2];        c.arr[3] = a.arr[3];         c.arr[4] = a.arr[1];        c.arr[5] = a.arr[0];    }    return c;}int bfs() {    memset(vis, 0, sizeof(vis));    queue<node> q;    q.push(s);    node tmp;     vis[change(s)] = 1;    while (!q.empty()) {        tmp = q.front();         q.pop();                    if (judge(tmp, e)) {            return tmp.d;        }        for (int i = 1; i <= 4; i++) {            node c;            c = turn(tmp, i);            if (!vis[change(c)]) {                c.d = tmp.d + 1;                 vis[change(c)] = 1;                q.push(c);            }         }    }     return -1;}int main() {    while (scanf("%d", &s.arr[0]) != EOF) {        for (int i = 1; i < MAXN; i++)             scanf("%d", &s.arr[i]);        for (int i = 0; i < MAXN; i++)             scanf("%d", &e.arr[i]);        printf("%d\n", bfs());    }        return 0;}

HDU5012-Dice (BFS)