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class Student extends Person{ String sID;

public Student(String n,String s,int a,String sid){ super(n,s,a); sID = sid; }

void showID(){

System.out.println(\ }}

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byte[] a1, a2[]; byte a3[][]; byte[][] a4;

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int a[] = {1, 2, 3};

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public class X6_1_5 {

public static void main(String[] args) { AB aa = new AB(); AB bb; bb = aa;

System.out.println(bb.equals(aa)); }}

class AB{ int x = 100; } A£®true

B£®false C£®±àÒë´íÎó D£®100

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6£®ÒÑÖªÓж¨Ò壺String s=\£¬ÏÂÃæÄĸö±í´ïʽÕýÈ·£¿£¨ A £© A£®s += \ B£®char c = s[1]; C£®int len = s.length; D£®String s = s.toLowerCase();

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6£®Êý×é³õʼ»¯°üÀ¨ ¾²Ì¬ ³õʼ»¯ºÍ ¶¯Ì¬ ³õʼ»¯Á½ÖÖ·½Ê½¡£ 7£®ÀûÓà System ÀàÖÐµÄ arraycopy() ·½·¨¿ÉÒÔʵÏÖÊý×éÔªËØµÄ¸´ÖÆ£»ÀûÓà Arrays ÀàÖÐµÄ sort() ºÍ binarySearch() ·½·¨¿ÉÒÔʵÏÖ¶ÔÊý×éÔªËØµÄÅÅÐò¡¢²éÕҵȲÙ×÷¡£ 8£®JavaÓïÑÔÌṩÁËÁ½ÖÖ¾ßÓв»Í¬²Ù×÷·½Ê½µÄ×Ö·û´®Àࣺ String ÀàºÍ StringBuffer Àà¡£ËüÃǶ¼ÊÇ java.lang.Object µÄ×ÓÀà¡£ Èý¡¢Ð´³öÏÂÁгÌÐòµÄÔËÐнá¹û 1£®public class X6_3_1 {

public static void main(String[] args) { int a[]={12,39,26,41,55,63,72,40,83,95}; int i1=0,i2=0;

for(int i=0;i

System.out.println(i1+\ }

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2£®public class X6_3_2 {

public static void main(String[] args) { int a[]={36,25,48,14,55,40,32,66}; int b1,b2; b1=b2=a[0];

for(int i=1;ib1 ){

if ( b1 >b2 ) b2=b1;

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b1=a[i]; }

System.out.println(b1+\ } } ¡¾ÔËÐнá¹û¡¿ 66 55

3£®public class X6_3_3 {

public static void main(String[] args) { int a[]={36,25,48,14,55,40,32,66 }; int b1,b2; b1=b2=a[0];

for (int i=1;i

if ( b1

System.out.println(b1+\ } }

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4£®public class X6_3_4 {

public static void main(String[] args) { String str = \ char[] a =str.toCharArray(); int i1 =0, i2=0, i;

for(i=0;i

System.out.println(i1+\ }}

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5£®public class X6_3_5 {

public static void main(String[] args) { String str =\ char[] a = str.toCharArray(); int b[] = new int[5],i; for(i=0;i

case 'a': b[0] ++; break; case 'b': b[1] ++; break; case 'c': b[2] ++; break; case 'd': b[3] ++; break;

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default : b[4] ++; } }

for(i =0; i<5; i++)

System.out.print(b[i]+\ System.out.println(); } }

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4 3 2 2 3

6£®public class X6_3_6 {

public static void main(String[] args) {

int a[] = {76,83,54,62,40,75,90,92,77,84}; int b[] = {60,70,90,101}; int c[]=new int[4],i;

for (i=0; i

while (a[i] >= b[j] ) j ++; c[j] ++; }

for (i=0; i<4; i++)

System.out.print(c[i]+\ System.out.println(); }

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public class X6_4_1 {

public static void main(String[] args) { int[] a = new int[20]; a[0]=0; a[1]=1; int i;

for(i=2;i<20;i++){ a[i]=a[i-1]+a[i-2]; // ÇóÆäÓà18Ïî }

for(i=0;i<20;i++){ // ÿһÐÐÏÔʾ5¸öÔªËØ if(i%5 == 0) System.out.println(); System.out.print(a[i]+\ }

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