阶乘在高中时都学过,比如说5的阶乘用数学表示就是5!,在写的通俗一点就是5 * 4 * 3 * 2 * 1。用一个数学公式表示就是n!=1 * 2 * 3 * …n。阶乘也可以用代码实现,Java中有三中循环结构,先看for循环的
import java.util.Scanner;
public class jiecheng {
public static void main(String[] args){
Scanner a = new Scanner(System.in);
System.out.println("请输入你要求的阶乘:");
int num = a.nextInt();
int sum = 1;
for (int i = 1;i<=num;i++){
sum*=i;
}
}
然后是while循环的
import java.util.Scanner;
public class jiecheng {
public static void main(String[] args){
Scanner a = new Scanner(System.in);
System.out.println("请输入你要求的阶乘:");
int num = a.nextInt();
int i = 1;
int sum = 1;
while(i<num){
i+=1;
sum*=i;
}
}
}
接下来是do–while循环结构的
import java.util.Scanner;
public class jiecheng {
public static void main(String[] args){
Scanner a = new Scanner(System.in);
System.out.println("请输入你要求的阶乘:");
int num = a.nextInt();
int sum = 1;
int i = 1;
do{
i+=1;
sum*=i;
}while(i<num);
System.out.println(num+"的阶乘为"+sum);
}
}