Java 二维整数数组洗牌
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2D int array shuffle
提问by Erazx
im new to this but im tring to do a hotel reservation program.
我是新来的，但我想做一个酒店预订计划。
So i have a 2D int array with ALL rooms, when i start the program i want them to be randomly shuffle in to an array called RoomNotInUse or RoomInUse (so evertime i start the program the rooms are randomly generated.
所以我有一个包含所有房间的 2D int 数组，当我启动该程序时，我希望它们随机进入一个名为 RoomNotInUse 或 RoomInUse 的数组（所以每次我启动程序时，房间都是随机生成的。
Would be awesome if anyone know a way around this :)
如果有人知道解决这个问题的方法，那就太棒了:)
// ARRAYS
protected static int[][] rooms = {
{1,1}, {1,2}, {1,3}, {1,4}, {1,5},
{2,1}, {2,2}, {2,3}, {2,4}, {2,5},
{3,1}, {3,2}, {3,3}, {3,4}, {3,5},
{4,1}, {4,2}, {4,3}, {4,4}, {4,5},
{5,1}, {5,2}, {5,3}, {5,4}, {5,5}
};
//Declare all hotel rooms 5x5, the first number is the floor and the sec is the room
private char[][] ROIU = {
};
//Rooms not in use
private char[][] RIU = {
};
//Rooms in use
public class roomShuffle {
}
//Shuffle all rooms in 2 diffrent arrays, ROIN and RIU
public class RoomNotInUse {
}
//Displayes all the rooms thats not in use
public class RoomInUse {
}
//Displayes all rooms in use
}
}
回答by Sajal Dutta
回答by Alessio
A generic shuffle method in Java should me similar to this
Java 中的通用 shuffle 方法应该与此类似
The important thing is that you have to swap an item with a random element that comes after in the collection ;)
重要的是，您必须将项目与集合中出现的随机元素交换；)
public void shuffle(Comparable [] a){
for(int i=0;i,a.length;i++)
swap(a,i,getRandom(i,a.length-1);
}
private int getRandom(int min, int max){
Random rnd = new Random();
return min + rnd.nextInt(max-min+1);
}
private void swap(Comparable [] a, int i, int j){
Comparable temp = a[i];
a[i]=a[j];
a[j]=temp;
}
Otherwise you can use the Collection.shuffle method.
否则，您可以使用 Collection.shuffle 方法。
回答by Masudul
Assign all array into list. Than use Collections.shuffle().
将所有数组分配到列表中。比用Collections.shuffle()。
List<int[]> pair=new ArrayList<int[]>();
pair.addAll(Arrays.asList(rooms));
Collections.shuffle(pair);
回答by bvitaliyg
You can use Fisher–Yates algorithm modified for two-dimensional arrays:
您可以使用针对二维数组修改的 Fisher–Yates 算法：
void shuffle(int[][] a) {
Random random = new Random();
for (int i = a.length - 1; i > 0; i--) {
for (int j = a[i].length - 1; j > 0; j--) {
int m = random.nextInt(i + 1);
int n = random.nextInt(j + 1);
int temp = a[i][j];
a[i][j] = a[m][n];
a[m][n] = temp;
}
}
}
回答by Oguzhan Cevik
Scanner scanner = new Scanner(System.in);
int n;
int m;
int selection;
System.out.println("Enter number of team");
n = scanner.nextInt();
m = (int) Math.sqrt(n);
int[][] matrix = new int[m][m];
List<Integer> listMatrix = new ArrayList<Integer>();
for (int i = 0; i < m; i++) {
for (int j = 0; j < m; j++) {
matrix[i][j] = i * m + j + 1;
System.out.print(matrix[i][j] + "\t");
}
System.out.println();
}
for (int i = 0; i < m * m; i++) {
listMatrix.add(i + 1);
}
System.out.println();
do {
System.out.println("what line is the card?");
selection = scanner.nextInt();
} while (!(selection >= 1 && selection <= m));
selection -= 1;
int[] values = new int[m];
for (int i = 0; i < m; i++) {
values[i] = matrix[selection][i];
// System.out.print(values[i] + "\t");
}
System.out.println();
Collections.shuffle(listMatrix);
for (int i = 0; i < m; i++) {
for (int j = 0; j < m; j++) {
matrix[i][j] = listMatrix.get(j + i * m);
System.out.print(matrix[i][j] + "\t");
}
System.out.println();
}
scanner.close();
