31.100 ~ 50000之间有多少整数，其各位数字之和为5，分别是哪些数（例如整数1324的各位数字之和为 1+3+2+4 等于10（不为5）），并统计满足条件的整数有多少个
package cutestFox;
public class Test022 {
public static void main(String[] args) {
int total = 0;
for (int i = 100; i <= 50000; i++) {
int a= i%10;
int b=(i/10)%10;
int c=(i/100)%10;
int d=(i/1000)%10;
int e = i/10000;
if (a+b+c+d+e==5) {
System.out.println(i);
total++;
}
}
System.out.println("满足条件的整数有:"+total+"個");
}
}
32.鸡兔同笼共80个头，208只脚，鸡和兔各有几只
package cutestFox;
public class Test020 {
public static void main(String[] args) {
for (int k = 0; k <= 80; k++) {
for (int i = 0; i <= 80; i++) {
if (4 * k + 2 * i == 208) {
if (k + i == 80) {
System.out.println("兔子：" + k);
System.out.println("鸡：" + i);
}
}
}
}
}
}
33.鸡翁一值钱五，鸡母一值钱三，鸡雏三值钱一。百钱买百鸡，问鸡翁、鸡母、鸡雏各几何
package cutestFox;
public class Test021 {
public static void main(String[] args) {
for(double a=0;a<=20;a++) {
for(double b=0;b<=33;b++) {
for(double c=0;c<=300;c=c+3) {
if((a*5+b*3+(c/3))==100) {//钱数为100
if(a+b+c==100)//鸡数为100
System.out.println("鸡翁："+a+"鸡母："+b+"鸡雏："+c);
}
}
}
}
}
}
34.(计算将来的学费）假设今年某一大学的学费为10000，学费增长率为5%，使用循环语句编程，计算10年的学费.
package cutestFox.github.io.execise01;
public class Code018 {
public static void main(String[] args) {
double tuition = 10000;
double rate = (5.0 / 100);
for (int i = 1; i <= 10; i++) {
System.out.println("第" + i + "年的学费为：" + tuition);
tuition += (tuition) * (1 + rate);
}
}
}
35.(求满足n>12000的最小数 n) 用while循环求n平方大于12000的最小数n
package cutestFox.github.io.execise01;
public class Code019 {
public static void main(String[] args) {
int n = 0;
while(n*n<12000) {
n++;
}
System.out.println("n的平方大于12000的最小整数为："+n);
}
}
36.(查找能被5和6整除的数)编写程序，显示从100到1000之间所有能够被5和6整除的数，每行显示10个
package cutestFox.github.io.execise01;
public class Code020 {
public static void main(String[] args) {
int counter = 0;
for(int i=100;i<1000;i++) {
if(i%5==0&i%6==0) {
counter++;
System.out.print(i+"\t");
if(counter%10==0)
System.out.println();
}
}
}
}
37.(求满足n<12000的最大数n)用while循环求n立方小于12000的最大数n
package cutestFox.github.io.execise02;
public class Code001 {
public static void main(String[] args) {
int n = 0;
while(n*n*n<12000) {
n++;
}
System.out.println("n的立方小于12000的最大整数为："+(n-1));
}
}
38.(显示ASCII字符表)编写程序，打印字符表中的128个字符。每行打印10个
package cutestFox.github.io.execise02;
public class Code002 {
public static void main(String[] args) {
int counter = 0;
for(int i=(int)('!');i<=(int)('~');i++ ) {
counter++;
System.out.print((char)i+"\t");
if(counter%10==0)
System.out.println();
}
}
}
39.打印图案I
package cutestFox.github.io.execise02;
public class Code003 {
public static void main(String[] args) {
for(int i=1;i<=6;i++) {
for(int j=1;j<=i;j++)
System.out.print(j+"\t");
System.out.println();
}
}
}
39.打印图案II
package cutestFox.github.io.execise02;
public class Code004 {
public static void main(String[] args) {
for(int i=6;i>=1;i--) {
for(int j=1;j<=i;j++)
System.out.print(j+"\t");
System.out.println();
}
}
}
40.猜数字游戏一个类A有一个成员变量v。定义一个类对A类的成员变量v进行猜。如果大了则提示大了小了则提示 小了。等于则提示猜测成功。
解法一：
import java.util.Random;
import java.util.Scanner;
public class A {
private Integer vv = 0;
public A() {
Random r = new Random();
vv = r.nextInt(1000);
}
public String guess (Integer parameter1) {
String res = "小了";
if(parameter1!=null) {
if(vv.compareTo(parameter1)==0)
res = "相等";
else if(vv.compareTo(parameter1)<0)
res = "大了";
}
return res;
}
public static void main(String[] args) {
A a = new A();
Scanner sc =new Scanner(System.in);
while(true) {
System.out.println("input:");
String ss = sc.nextLine();
if("quit".equalsIgnoreCase(ss))
break;
try {
int kk = Integer.parseInt(ss);
String res = a.guess(kk);
if("相等".equals(res)) {
System.out.println("reight…………");
break;
}
else {
System.out.println(res);
}
} catch (Exception e) {
System.out.println("不合法的輸入");
}
}
}
}
解放二：
import java.util.Random;
import java.util.Scanner;
public class A {
private int v=0;
public A() {
Random r = new Random();
v = r.nextInt(1000);
}
public int Guess() {
Scanner sc = new Scanner(System.in);
System.out.println("請輸入你猜的數：");
int xx = sc.nextInt();
while(true) {
if(xx>v) {
System.out.println("猜大了！");
}
if(xx<v) {
System.out.println("猜小了");
}
xx = sc.nextInt();
if(v==xx) {
System.out.println("恭喜你猜対了！！");
}
if(v==xx)
break;
}
return xx;
}
public static void main(String[] args) {
A a = new A();
a.Guess();
}
}