请问此段程序中将提示用户输入Y代表是N代表否后怎么改写程序，谢谢！

Question

package com.imooc;import java.util.Scanner;public class GuessBirthday3 { public static void main(String[] args) { String set1= " 1  3  5  7\n"+ " 9 11 13 15\n"+ "17 19 21 23\n"+ "25 27 29 31"; String set2= " 2  3  6  7\n"+ "10 11 14 15\n"+ "18 19 22 23\n"+ "26 27 30 31"; String set3= " 4  5  6  7\n"+ "12 13 14 15\n"+ "20 21 22 23\n"+ "28 29 30 31"; String set4= " 8  9 10 11\n"+ "12 13 14 15\n"+ "24 25 26 27\n"+ "28 29 30 31"; String set5= "16 17 18 19\n"+ "20 21 22 23\n"+ "24 25 26 27\n"+ "28 29 30 31"; int day=0; Scanner input=new Scanner(System.in); System.out.print("Is your birthday in Set1?\n"); System.out.print(set1); System.out.print("\nEnter 0 for no and 1 for Yes: "); int answer=input.nextInt(); if(answer==1)     day+=1; System.out.print("Is your birthday in Set2?\n"); System.out.print(set2); System.out.print("\nEnter 0 for No and 1 for Yes: "); answer=input.nextInt(); if(answer==1) day+=2; System.out.print("Is your birthday in Set3?\n"); System.out.print(set3); System.out.print("\nEnter 0 for No and 1 for Yes: "); answer=input.nextInt(); if(answer==1) day+=4; System.out.print("Is your birthday in Set4?\n"); System.out.print(set4); System.out.print("\nEnter 0 for No and 1 for Yes: "); answer=input.nextInt(); if(answer==1) day+=8; System.out.print("Is your birthday in Set5\n?"); System.out.print(set5); System.out.print("\nEnter 0 for No and 1 for Yes: "); answer=input.nextInt(); if(answer==1) day+=16; System.out.println("Your birthday is "+ day +"!"); }}