java遇见cannot be resolved or is not a field怎么解决

package zy03;
import java.util.Scanner;
import java.util.Random;
public class DEMO {

public static void main(String[] args) {
    // TODO Auto-generated method stub
    int rand=(int)(Math.random()*30)+20;
    int count=0;
    Scanner input=new Scanner(System.in);
    int guess;
    do {
        guess=input.nextInt;
        if(rand>guess) {
            System.out.println("猜小了");
            count++;
            }
        else if(rand<guess){
            System.out.println("猜大了");
            count++;
        }else {
        count++;
        break;}
    }while(count<5);
    System.out.println("猜对了");
}

}