二维数组顺时针输出

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*/

package javaapplication1;

/**
*
* @author YJZ
*/
public class PrintMatrixClockwisely {

public static void PrintMatrix(int a[][],int columns,int rows){
if(a==null||columns<=0||rows<=0){
System.out.print("输入错误");
}
int start =0;
while(columns>start*2&&rows>start*2){
PrintMatrixInCircle(a,columns,rows,start);
start++;
}
}
public static void PrintMatrixInCircle(int a[][],int columns,int rows,int start){
int endX=rows-1-start;
int endY=columns-1-start;
//从左到右
for(int i=start;i<=endX;i++){
int number=a[start][i];
PrintNumber(number);
}
//从上到下
if(start<endY){
for(int i=start+1;i<=endY;i++){
int number=a[i][endX];
PrintNumber(number);
}
}
//从右到左
if(start<endX&&start<endY){
for(int i=endX-1;i>=start;--i){
int number=a[endY][i];
PrintNumber(number);
}
}
//从下到上
if(start<endX&&start<endY-1){
for(int i=endY-1;i>=start;--i){
int number=a[i][start];
PrintNumber(number);
}
}
}
public static void PrintNumber(int number) {
System.out.print(number+" ");
}
public static void Text(int columns,int rows){
int[][] aa=new int[columns][rows];
int b=1;
for(int i=0;i<columns;i++){
for(int j=0;j<rows;j++){
aa[i][j]=b;
b++;
}
}
PrintMatrix(aa,columns,rows);
System.out.println(" ");
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
Text(4,1);
Text(1,4);
Text(4,4);
Text(1,1);
}
}