Rewrite following Java program using use List and not arrays.

public class Shoes {

    private String name;
    private int size;
    private String model;

    public Shoes() {
    }

    public Shoes(String name, int size, String model) {
        this.name = name;
        this.size = size;
        this.model = model;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getSize() {
        return size;
    }

    public void setSize(int size) {
        this.size = size;
    }

    public String getModel() {
        return model;
    }

    public void setModel(String model) {
        this.model = model;
    }

    @Override
    public String toString() {
        return "name='" + name + '\'' + ", size=" + size + ", model='" + model + '\'';
    }

    public static void main(String[] args) {
        Shoes[] shoes = new Shoes[5];
        shoes[0] = new Shoes("Nike1", 9, "Nike");
        shoes[1] = new Shoes("ASICS2", 12, "ASICS");
        shoes[2] = new Shoes("Adidas8", 11, "Adidas");
        shoes[3] = new Shoes("Saucony7", 6, "Saucony");
        shoes[4] = new Shoes("Brooks5", 8, "Brooks");

        for (int i = 0; i < shoes.length; i++) {
            System.out.println(shoes[i]);
        }
    }
}

Every time I attempt to execute this, I get an inputmismatchexception, which looks like this:
Oops! Read Exception: java.util.InputMismatchExceptionInitial input:
Input sorted by grade
Input sorted selection

This is my code.

import java.util.*;  
import java.io.*;
import java.io.PrintStream;

public class jack {

PrintStream prt = System.out;
int n;
int i;
int j;
double grade[];
String name[];
jack() {

try {
Scanner inf = new Scanner(System.in);
n=inf.nextInt();
inf.nextLine();
grade=new double[n];
name = new String[n];
for (int i=0; i<n; i++){
name[i] = inf.next();
inf.nextLine();
grade[i] = inf.nextDouble();
inf.nextLine();
}
inf.close();
} catch (Exception e) {
prt.printf("\nOops! Read Exception: %s", e);
}
  
}

  
  
private void print() {

for(int i=0; i<n; i++)
{
System.out.println(name[i]+" "+grade[i]);
}
System.out.println();

}
private void sortbyname(){
String minStudent;
int index;
for(int i=0;i<n-1;i++){
minStudent=name[i];
index=i;
  
for(int j=i+1; j<n; j++){
if(name[j].compareTo(minStudent)<0)
{
minStudent = name[j];
index =j;
}
}
String beforewrd = name[index];
name[index]=name[i];
name[i]=beforewrd;   
}
  
}
private void sortbygrade(){
  
for(int i=0;i<n;i++){
int index=i;
for(int j=i+1; j<n; j++){
if(grade[j]<grade[i]){
index = j;
}
}
double smallNum = grade[index];
grade[index] = grade[i];
grade[i]=smallNum;
}
}

public static void main(String args[]) throws Exception{
jack p = new jack ();
System.out.print("Initial input:");
p.print();
  
p.sortbyname();
System.out.print("Input sorted by grade");
p.print();
  
p.sortbygrade();
System.out.print("Input sorted selection");
p.print();
  
  

}
}

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