java定义二维数组的几种写法（转）

浅浅的花香味﹌ 2021-06-24 14:35 308阅读 0赞

//定义二维数组写法1

class numthree  
\{  
public static void main(String\[\] args)  
\{  
float\[\]\[\] numthree;             //定义一个float类型的2维数组  
numthree=new float\[5\]\[5\];       //为它分配5行5列的空间大小  
numthree\[0\]\[0\]=1.1f;            //通过下标索引去访问     1行1列=1.1  
numthree\[1\]\[0\]=1.2f;                                  // 2行1列=1.2  
numthree\[2\]\[0\]=1.3f;                                  // 3行1列=1.3  
numthree\[3\]\[0\]=1.4f;                                  // 4行1列=1.4  
numthree\[4\]\[0\]=1.5f;                                  // 5行1列=1.5  
System.out.println(numthree\[0\]\[0\]); //打印换行输出喽  
System.out.println(numthree\[1\]\[0\]);  
System.out.println(numthree\[2\]\[0\]);  
System.out.println(numthree\[3\]\[0\]);  
System.out.println(numthree\[4\]\[0\]);  
\}  
\}

//定义二维数组写法2   定义的同时分配空间大小  
class numfour  
\{  
public static void main(String\[\] args)  
\{  
   short\[\]\[\] numfour=new short\[5\]\[8\]; //定义一个short类型的数组同时为它分配5行8列的空间大小  
   numfour\[0\]\[7\]=10;  
   numfour\[1\]\[6\]=20;  
   numfour\[2\]\[5\]=30;  
   numfour\[3\]\[4\]=40;  
   numfour\[4\]\[3\]=50;  
   System.out.println(numfour\[0\]\[7\]);  
   System.out.println(numfour\[1\]\[6\]);  
   System.out.println(numfour\[2\]\[5\]);  
   System.out.println(numfour\[3\]\[4\]);  
   System.out.println(numfour\[4\]\[3\]);  
\}  
\}

//定义二维数组写法3        不规则数组  
class numfive  
\{  
public static void main(String\[\] args)  
\{  
long\[\]\[\] numfive=new long\[5\]\[\];     //定义一个long类型的不规则数组  
numfive\[0\]=new long\[5\];             //为第1行分配5列  
numfive\[1\]=new long\[6\];             //为第2行分配6列  
numfive\[2\]=new long\[7\];             //为第3行分配7列  
numfive\[3\]=new long\[8\];             //为第4行分配8列  
numfive\[4\]=new long\[9\];             //为第5行分配9列

numfive\[0\]\[4\]=10000000000L;         //1行5列=10000000000  
numfive\[1\]\[5\]=20000000000L;         //2行6列=20000000000  
numfive\[2\]\[6\]=30000000000L;         //3行7列=30000000000  
numfive\[3\]\[7\]=40000000000L;         //4行8列=40000000000  
numfive\[4\]\[8\]=50000000000L;         //5行9列=50000000000

System.out.println(numfive\[0\]\[4\]); //打印换行输出喽  
System.out.println(numfive\[1\]\[5\]);  
System.out.println(numfive\[2\]\[6\]);  
System.out.println(numfive\[3\]\[7\]);  
System.out.println(numfive\[4\]\[8\]);  
System.out.println(numfive\[4\]\[7\]); //打印输出一个没有定义数组元素的数组 java会自动将他初始化值为0  
\}  
\}

//定义2维数组写法4    定义的同时赋初始值  
class numsix  
\{  
public static void main(String\[\] args)  
\{  
double\[\]\[\] numsix=\{ \{1.111D,2.222D,3.333D\},\{4.444D,5.555D,6.666D\}\};//定义double型的数组分配3行3列的空间同时赋值  
System.out.println(numsix\[0\]\[0\]); //打印换行输出1行1列=1.111  
System.out.println(numsix\[1\]\[1\]); //打印换行输出2行2列=5.555  
\}  
\}

//定义2维数组写法5   定义不规则的2维数组同时赋初始值  
class numseven  
\{  
public static void main(String\[\] args)  
\{  
int\[\]\[\] numseven=new int\[\]\[\]\{ \{10,20,30\},\{40,50\},\{60\}\}; //没什么好说的如果你在看不懂 那就别学了！  
System.out.println(numseven\[0\]\[2\]);  
System.out.println(numseven\[1\]\[1\]);  
System.out.println(numseven\[0\]\[0\]);  
\}  
\}

//定义2维数组写法6 定义不规则的2维数组同时赋初始值；  
class numeight  
\{  
public static void main(String\[\] args)  
\{  
int\[\]\[\] numeight=\{ \{100,200,300,400\},\{500,600,700,800\},\{900,1000,1100,1200,1300\}\};  
System.out.println(numeight\[0\]\[2\]);  
System.out.println(numeight\[1\]\[2\]);  
System.out.println(numeight\[2\]\[1\]);  
\}  
\}