Bday finder using input java [duplicate] - java

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 1 year ago.
why isnt this working
package com.company;
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
// write your code here
Scanner scan = new Scanner(System.in);
System.out.println("enter year: ");
int year = scan.nextInt();
int age = 0;
System.out.println("is your bday complete this year: ans 'Y/N'");
String bday= scan.nextLine();
scan.close();
if (bday=="Y"||bday=="y"){
age = 2021-year;
}else if(bday=="N"||bday=="n"){
age = 2020-year;
}else{
System.out.println("wrong input");
}
System.out.println(age);
}
}

You need to use equals() method to compare strings. In this case it is better to use equalsIgnoreCase(). Update the if and else if as below:
if (bday.equalsIgnoreCase("y")){
age = 2021-year;
}else if(bday.equalsIgnoreCase("n")){
age = 2020-year;
}

Related

String how to validate space [duplicate]

This question already has answers here:
Scanner doesn't see after space
(7 answers)
Closed 2 years ago.
this is my code, it can validate single word but when i input example: John Smith the output is just John
package space;
import java.util.Scanner;
public class validate{
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
boolean cusloop=false;
String cusname="";
while(cusloop==false){
System.out.print("Enter customer name: ");
cusname=sc.next();
if(cusname.matches("[a-zA-Z ]+")){
cusloop=true;
}
else{
System.out.println("Invalid Input!");
System.out.println("Input Letters Only!");
}
}
}
}
just change
cusname = sc.nextLine();

If else statement not working JAVA [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 7 years ago.
The line starting the if statement is causing me issues. When I run it it will ask me my gender, I say boy and it says 'you cannot enter'. It doesnt even ask for the age!
import java.util.Scanner;
class Apples {
//////Main Method
public static void main (String[] args) {
if (Apples.getGender() == "boy" && Apples.getAge() > 17) {
System.out.printf("You can enter");
}
else {
System.out.printf("You cannot enter");
}
}
/////Two Methods
public static String getGender() {
Scanner newGender = new Scanner(System.in);
System.out.println("What gender are you?");
String genderMF = newGender.nextLine();
return genderMF;
}
public static int getAge() {
Scanner newAge = new Scanner(System.in);
System.out.println("What age are you?");
int ageMF = newAge.nextInt();
return ageMF;
}
}
You have to compare strings with .equals function in Java, not with ==.
s1.equals(s2);

Calculator no work [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 8 years ago.
Could some one please tell me why this calculator isn't working ? It just doesn't provide an awnser.
import java.util.Scanner;
public class Calcu {
public static void main( String[] args )
{
Scanner mati = new Scanner(System.in);
System.out.println("This program adds up or substracts two numbers");
System.out.println("Enter an operator");
String letter = mati.next(); //WAITS FOR THE PHRASE ADD OR SUBSTRACT
System.out.println("Enter your first number");
int userNumberone = mati.nextInt(); // Get's first Number
System.out.println("Enter your second number");
int userNumbertwo = mati.nextInt(); //Get's Following Number
if(letter == "add") {
int result = userNumberone + userNumbertwo;
System.out.println(result);
} else if(letter == "substract") {
int result1 = userNumberone - userNumbertwo; //If statement to add or substract.
System.out.println(result1);
}
}
}
You should use letter.equals("add") instead of letters == "add". This is explained here: How do I compare strings in Java?

DoWhile in Java [duplicate]

This question already has answers here:
How do I compare strings in Java?
(23 answers)
Closed 8 years ago.
When I try to do a dowhile loop in Java with a string it just terminates the program without an error not giving me a chance to enter if I would like to continue. How do I make my program loop if requested using a string?
public static void main(String args[]) {
Scanner user_input = new Scanner (System.in);
Maths math = new Maths();
double firstNum, secondNum;
String calcAgain = null;
do{
System.out.println("Enter First Number: ");
firstNum = user_input.nextDouble();
System.out.println("Enter Second Number: ");
secondNum = user_input.nextDouble();
System.out.println("Please select an operation! (+,-,*,/)");
String operation = user_input.next();
if (operation.equals("+")) {
System.out.println(math.add(firstNum, secondNum));
}
else if (operation.equals("-")) {
System.out.println(math.subtract(firstNum, secondNum));
}
else if (operation.equals("*")) {
System.out.println(math.multiply(firstNum, secondNum));
}
else if (operation.equals("/")) {
System.out.println(math.divide(firstNum, secondNum));
}
else {
System.out.println("Invalid Function!");
}
System.out.println("Would you like to do another calculation? ");
calcAgain = user_input.nextLine();
}while(calcAgain == "yes");
You might want to look at string operations for equality. The condition while(calcAgain == "yes") will not execute ever, because you are comparing the object itself. String equality is done with the .equals() function.

error with inputting string using sc.nextLine [duplicate]

This question already has answers here:
Scanner issue when using nextLine after nextXXX [duplicate]
Using scanner.nextLine() [duplicate]
(5 answers)
Closed 8 years ago.
import java.util.Scanner;
public class GpaConverterTester
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
GpaConverter g = new GpaConverter();
System.out.println("How many classes are you taking? ");
int classAmount = sc.nextInt();
while(classAmount > 0)
{
System.out.println("Enter Grade: ");
String grade = sc.nextLine();
g.setGpaValue(grade);
classAmount--;
}
System.out.println("Average: " + g.getAverage());
}
}
My basic problem is that it wont let me enter in the grade string. This is what happens...
Output:
"How many classes are you taking?
2
Enter Grade:
Enter Grade:
"
It does not let me enter in the grade string.
Thank you for helping!
I figured it out.
Use sc.next() instead of line.

Categories

Resources