area.java

java知识,以及java的设置和编程等.这个需要解压缩才可以看到.希望有用啊!

/*
 * Created on 2003/12/16
 *
 * To change the template for this generated file go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */

/**
 * @author zhaoz
 *
 * To change the template for this generated type comment go to
 * Window>Preferences>Java>Code Generation>Code and Comments
 */
public class area {
	public static void main(String args[]){
		double pi,r,a,c,d;
		r=10.8;
		pi=3.1416;
		a=pi*r*r;
		c=3.0;
		d=4.0;
		System.out.println("area of circle: " + a);
		char ch1,ch2;
		ch1=88;
		ch2='Y';
		System.out.println("ch1 and ch2 " + ch1 + " " + ch2);
		ch1='X';
		System.out.println("ch1 " + ch1);
		ch1++;
		System.out.println("ch1 now " + ch1);
		ch1='\123';
		System.out.println("ch1 now " + ch1);
		ch1='\u3540';
		System.out.println("ch1 now " + ch1);
		ch1='\r';
		System.out.println("ch1 now " + ch1);
		ch1='\t';
		System.out.println("ch1 now " + (int)ch1);
		ch1='\b';
		System.out.println("ch1 now " + (int)ch1);
		ch1='\f';
		System.out.println("ch1 now " + (int)ch1);
		a=Math.sqrt(c*c+d*d);
		System.out.println("a now " + a);
		int e=257;
		byte f;
		f=(byte)e;
		System.out.println("f now " + f);
		e=10000%256;
		System.out.println("e now " + e);
		f=(byte)pi;
		System.out.println("pi now " + f);
		byte aa,bb,cc;
		aa=125;
		bb=125;
		cc=100;
		e=aa*bb*cc;
		System.out.println("e now " + e);
		aa=50;
		aa=(byte)(aa*2);
		System.out.println("aa now " + aa);
		int[][] twoD;
		twoD=new int[4][];
		for(int i=0;i<4;i++){
			twoD[i]=new int[i+1];
		}
		int i,j,k=1;
		for(i=0;i<4;i++){
			for(j=0;j<i+1;j++){
				twoD[i][j]=k;
				k++;
			}
		}
		for(i=0;i<4;i++){
			for(j=0;j<i+1;j++){
				System.out.print(twoD[i][j] + " ");
			}
			System.out.println();
		}
	}
}