java输出hello world_怎么样用Java程序输出“Hello World,”
import java.util.ArrayList;import java.util.List;
import java.util.Scanner;
public class Test { public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
System.out.println("please enter a num : ");
int num = scan.nextInt();
System.out.println("factorial : " + compute(num,"*"));
System.out.println("sum : " + compute(num,"+"));
}
public static int m3(int num,String sign){
if(num == 1){
return num;
}
return sign.charAt(0) == + ? num + m3(num - 1,sign) : sign.charAt(0) == * ? num * m3(num - 1,sign) : 0;
}
public static long compute(int num,String sign){
long res = 1;
if (sign.charAt(0) == +) {
for (int i = 1; i <= num; i++) {
res += m3(i,sign);
}
res --;
}else if(sign.charAt(0) == *){
for (int i = 1; i <= num; i++) {
res *= m3(i,sign);
}
}else{
return -1;
}
return res;
}
}
取消
评论
import java.util.ArrayList;import java.util.List; import java.util.Scanner; public class Test { public static void main(String[] args) { Scanner scan = new Scanner(System.in); System.out.println("please enter a num : "); int num = scan.nextInt(); System.out.println("factorial : " + compute(num,"*")); System.out.println("sum : " + compute(num,"+")); } public static int m3(int num,String sign){ if(num == 1){ return num; } return sign.charAt(0) == + ? num + m3(num - 1,sign) : sign.charAt(0) == * ? num * m3(num - 1,sign) : 0; } public static long compute(int num,String sign){ long res = 1; if (sign.charAt(0) == +) { for (int i = 1; i <= num; i++) { res += m3(i,sign); } res --; }else if(sign.charAt(0) == *){ for (int i = 1; i <= num; i++) { res *= m3(i,sign); } }else{ return -1; } return res; } } 取消 评论