麻烦各位大神帮忙看一下，为什么报错

package project6;
import java.util.Arrays;
import java.util.Scanner;
public class Hello{
    int[] price;
    int num;
    static String name;
    Scanner input=new Scanner(System.in);
    public Hello(){
        for(int i=0;i<num;i++){
            System.out.println("请输入第"+(i+1)+"个"+name+"笔的价格");
            price[i]=input.nextInt();
         }
         System.out.println(name+"笔的价格为："+Arrays.toString(price));
     }
     {
         num=3;
     }
     static{
         name="英雄";
     }
     public static void main(String args[]){
          Hello a=new Hello();
     }
}