蓝桥杯 基础练习 Sine之舞 Java 递归

import java.util.Scanner;

public class Main {

public static void main(String[] args) {

System.out.println(Sn(new Scanner(System.in).nextInt(),1));

}
public static String Sn(int x,int y) {
if (x<=1) {
return An(x)+"+"+y;
}
return "("+Sn(x-1,y+1)+")"+An(x)+"+"+y;
}

public static String An(int x) {
return Sin(x,1);
}

public static String Sin(int x,int i) {

if (x<=1) {
return "sin("+(x+i-1)+")";
}
return "sin("+(i)+(i%2==0?"+":"-")+Sin(x-1,i+1)+")";
}
}