今日进行了习题练习
1、输出三个数中的最大值和最小值
import java.util.Scanner;
public class Homework6 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
System.out.println("请输入第一个数:");
int num1 =sc.nextInt();
System.out.println("请输入第二个数");
int num2 = sc.nextInt();
System.out.println("请输入第三个数");
int num3 = sc.nextInt();
// int max1=(num1 > num2 ? num1 : num2);
// int max2=(max1 > num3 ? max1 : num3);
// int min1=(num1 < num2 ? num1 : num2);
// int min2=(min1 < num3 ? min1 : num3);
// System.out.println("(" +num1+ "," +num2+ "," +num3+ ")的最大值为" +max2+ ",最小值// 为" +min2);
//Math数学库
int max=Math.max(num1, num2);
max=Math.max(max, num3);
int min=Math.min(num1, num2);
min=Math.min(min, num3);
System.out.println("最大值为:"+max+",最小值为"+min);
}
}
2、输出1-100的奇数(每行输出6个)
public class Homework7 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int a = 0;
for (int i = 1; i <= 100; i++) {
if (i%2 == 1) {
a++;
System.out.print(i+"t");
}
if (a%6 == 0) {
System.out.print("n");
}
}
}
}
3、1-100求和(for while以及do/while的写法)
public class Homework8 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int res = 0;
for(int i = 1;i <101;i++) {
res +=i;
}
System.out.println("1+2+3+...+100=" +res);
}
}
public class Homework81 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int a = 1;
int b = 0;
while(a < 101) {
b += a++;
}
System.out.println("1+2+3+...+100=" +b);
}
}
public class Homework82 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int a = 1;
int b = 0;
do {
b += a++;
}while(a < 101);
System.out.println("1+2+3+...+100=" +b);
}
}
4、1-100奇数求和
public class Homework9 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int res = 0;
for(int i = 1;i <101;i++) {
if(i%2 != 0) {
res +=i;
}
}
System.out.println("1+3+5+...+99=" +res);
}
}
5、1~100可以被3整除的数
public class Homework10 {
public static void main(String[] args) {
// TODO Auto-generated method stub
for(int con = 1;con <= 100;con++) {
if(con%3 == 0) {
System.out.println(con);
}
}
}
}
6、求100 以内所有能被3 整除但不能被5 整除的个数
public class Homework11 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int i = 0;
for(int con = 1;con <= 100;con++) {
if(con%3 == 0 && con%5 != 0) {
i++;
}
}
System.out.println("100以内所有能被3整除但不能被5整除的个数为" +i+ "个");
}
}
7、打印出所有的水仙花数
public class Shuixian {
public static void main(String[] args) {
// TODO Auto-generated method stub
for(int n = 100;n < 1000;n++) {
int a=n%10; //个位
int b=n/10%10;//十位
int c=n/100; //百位
if(Math.pow(a, 3)+Math.pow(b, 3)+Math.pow(c, 3) == n) {
System.out.println(n);
}
}
}
}
public class Test18 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int n = 100;
do {
int a=n%10; //个位
int b=n/10%10;//十位
int c=n/100; //百位
if(Math.pow(a, 3)+Math.pow(b, 3)+Math.pow(c, 3) == n) {
System.out.println(n);
}
}while(n++ < 999);
}
}
8、判断一个数是否质数
import java.util.Scanner;
public class Zhishu {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
System.out.println("请输入一个大于1的整数");
int n = sc.nextInt();
boolean sushu = true;
if(n == 1 || n % 2 == 0 && n != 2) {
sushu = false;
}
else {
for(int i = 2; i < n; i++ ) {
if(n % i == 0) {
sushu = false;
break;
}
}
}
if(sushu) {
System.out.println("是素数");
}
else {
System.out.println("不是素数");
}
}
}
9、编程求出自然数101-205中的所有质数
public class Test19 {
public static void main(String[] args) {
// TODO Auto-generated method stub
int cc=0;
for (int i = 101; i <= 205; i++) {
boolean bb=true;
for(int k=2;k
12、输入两个正整数m和n，求其最大公约数和最小公倍数
import java.util.Scanner;
public class Test1 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
int k1 = 0;
System.out.println("请输入第一个正整数：");
while(true) {
k1 = sc.nextInt();
if(k1 <=0) {
System.out.println("输入数据不合法，请重新输入！");
}else {
break;
}
}
int k2 = 0;
System.out.println("请输入第二个正整数：");
while(true) {
k2 = sc.nextInt();
if(k2 <=0) {
System.out.println("输入数据不合法，请重新输入！");
}else {
break;
}
}
int yueshu = -1;
int min = Math.min(k1, k2);
for(int k = min;k > 1;k--) {
if(k1%k == 0 && k2%k == 0) {
yueshu = k;
break;
}
}
int beishu = -1;
int max = Math.max(k1, k2);
for(int k = max;k < k1*k2;k++) {
if(k%k1 == 0 && k%k2 == 0) {
beishu = k;
break;
}
}
if(yueshu==-1)
System.out.println(k1+"和"+k2+"互质");
else
System.out.println(k1+"和"+k2+"的最大公约数"+yueshu);
if(beishu!=-1)
System.out.println(k1+"和"+k2+"的最小公倍数"+beishu);
}
}
import java.util.Scanner;
public class Homework12 {
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
System.out.println("输入第一个正整数");
int m = sc.nextInt();
System.out.println("输入第二个正整数");
int n = sc.nextInt();
int c = 1;
for (int i = 2; i <= Math.min(m, n); i++) {
if (m % i == 0 && n % i == 0) {
c *= i;
m = m / i;
n = n / i;
i--;
}
}
System.out.println("最大公约数：" + c);
System.out.println("最小公倍数：" + (c * m * n));
}
}
