Java中的動態定義數組
1.一維矩陣的動態定義(程式碼注釋)
1.1方法一
package dongtai; import java.util.Scanner; import java.util.ArrayList; public class DongTai { public static void main(String[] args) { Scanner scan = new Scanner(System.in); ArrayList<Integer> p = new ArrayList<>(); //創建一個ArrayList int n = scan.nextInt(); for(int i=0; i<n+1; i++) { p.add(0); //往p數組裡面添加元素 } for(int j=0; j<n+1; j++) { p.set(j, scan.nextInt()); //鍵盤端輸入數組的元素大小 }
1.2方法二(多維數組也可用這種方法)
package dongtai; import java.util.Scanner; public class DongTai { public static int []p; //直接定義一個一維數組 public static void main(String[] args) { Scanner scan = new Scanner(System.in); int num = scan.nextInt(); p = new int[num]; //可直接定義數組大小 } }
2.二維數組
package dongtai; import java.util.Scanner; public class DongTai { public static void main(String[] args) { Scanner scan = new Scanner(System.in); int n = scan.nextInt(); int [][] m; m = new int[n][]; for(int i=1; i<n; i++) //前兩個n位第一維,後兩個n為第二維 { m[i] = new int[n]; //動態創建第二維 for(int j=1; j<n; j++) { m[i][j] = 0; } } } }
3.二維數組與多維數組(1.2方法二)
package dongtai; import java.util.Scanner; public class DongTai { public static int arr[][][]; public static void main(String[] args) { Scanner scan = new Scanner(System.in); int n = scan.nextInt(); arr = new int[n][n][n]; } }


