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1.初识数组
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package step1;
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public class HelloWorld {
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public static void main(String[] args) {
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/********** Begin **********/
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int[] scores = {91,88,60};
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System.out.println("数组的第一个值为："+scores[0]); //在这里输出数组的第一个值
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System.out.println("数组的第二个值为："+scores[1]); //在这里输出数组的第二个值
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System.out.println("数组的第三个值为："+scores[2]); //在这里输出数组的第三个值
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/********** End **********/
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}
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}
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2.数组的使用
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package step2;
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import java.util.Scanner;
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public class HelloWorld {
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public static void main(String[] args) {
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/********** Begin **********/
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//在这里定义一个长度为4的字符串数组，用来存放学生姓名
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String[] stuNames = new String[4];
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//在这里给stuNames数组赋值 分别为 张三,张无忌,张三丰,张岁山
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stuNames[0] = "张三";
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stuNames[1] = "张无忌";
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stuNames[2] = "张三丰";
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stuNames[3] = "张岁山";
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//在这里输出stuNames数组中的数据
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System.out.println("数组中的第一个数据为：" +stuNames[0] );
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System.out.println("数组中的第二个数据为：" + stuNames[1]);
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System.out.println("数组中的第三个数据为：" + stuNames[2]);
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System.out.println("数组中的第四个数据为：" + stuNames[3]);
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int[] scores;
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Scanner sc = new Scanner(System.in);
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//在这里使用Scanner获取系统输入的整数,并用获取到的数据来设置scores数组的长度
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int length = sc.nextInt();
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scores = new int[length];
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/********** End **********/
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System.out.println("数组scores的长度为：" + scores.length);
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}
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}
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3.选择题
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double[] num=new double[];
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程序出错了
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ABCD
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4.数组练习-平均值和最大值
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package step3;
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import java.util.Scanner;
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public class HelloWorld {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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int[] scores = new int[sc.nextInt()];
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//循环给数组赋值
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for(int i = 0 ; i< scores.length;i++){
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scores[i] = sc.nextInt();
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}
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/********** Begin **********/
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//在这里计算数组scores的平均值和最大值
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float sum = 0;
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int max = scores[0];
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float avg;
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for(int i = 0; i < scores.length; i++){
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sum = sum + scores[i];
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}
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for(int i = 1; i < scores.length; i++){
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if(scores[i]>scores[i-1]){
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max = scores[i];
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}else{
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break;
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}
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}
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avg = sum / scores.length;
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System.out.println("平均值："+avg);
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System.out.println("最大值："+max);
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/********** End **********/
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}
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}
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5.二维数组
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package step4;
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public class HelloWorld {
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public static void main(String[] args) {
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/********** Begin **********/
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int[][] scores = {{92,85},{91,65},{90,33}};
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for(int i=0; i<scores.length; i++){ //行循环次数scores.length（每一列的长度）
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for(int j=0; j<scores[i].length; j++){ //列循环次数scores[i].length（每一行的长度）
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System.out.println(scores[i][j]);
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}
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//System.out.println();
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}
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//scores[][] = {{1,2},{1,2},{1,2}}; //是错误的
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for(int i=0; i<scores.length; i++){
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scores[i][0] = 1;
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scores[i][1] = 2;
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}
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for(int i=0; i<scores.length; i++){ //行循环次数
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for(int j=0; j<scores[i].length; j++){ //列循环次数
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System.out.println(scores[i][j]);
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}
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//System.out.println();
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}
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/********** End **********/
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}
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}
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6.选择题（2）
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6；编译不通过 |
