四平方和（Java）（循环）

import java.util.Scanner;
public class Main {
 public static void main(String[] args) {
  Scanner sc=new Scanner(System.in);
  int n=sc.nextInt();
  int a,b,c,d;
  int sqrt=(int) Math.sqrt(n);
  for(a=0;a<=sqrt;a++)
   for (b = a; b<=sqrt; b++) 
    for (c= 0; c<=sqrt; c++) 
     for (d= 0; d<=sqrt; d++) 
     if(n==a*a+b*b+c*c+d*d)
     {
      if(c>d)
      {
       int temp=d;
       d=c;
       c=temp;
      }
      System.out.print(a+" "+b+" "+c+" "+d);
      return;
     }
 }
}

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