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Start your free trialGabriel Favela
1,565 PointsNeed some help with charAt...
What the challenge is asking me to do is to return a 1 if the last name is between 'A' thru 'M', and return a 2 if it is between 'N' thru 'Z'. My code isn't compiling, I tried other ways of doing this but it keeps giving me syntax errors. I am a little stuck with this and don't want to waste more time then I already have. "you learn by asking"...
public class ConferenceRegistrationAssistant {
/**
* Assists in guiding people to the proper line based on their last name.
*
* @param lastName The person's last name
* @return The line number based on the first letter of lastName
*/
public int getLineNumberFor(String lastName) {
int lineNumber = 0;
/*
lineNumber should be set based on the first character of the person's last name
Line 1 - A thru M
Line 2 - N thru Z
*/
if (lastName.charAt('a' <= 'm')) {
lineNumber = 1;
}
if (lastName.charAt('n' <= 'z')) {
lineNumber = 2;
}
return lineNumber;
}
}
public class Example {
public static void main(String[] args) {
/*
IMPORTANT: You can compare characters using <, >. <=, >= and == just like numbers
*/
if ('C' < 'D') {
System.out.println("C comes before D");
}
if ('B' > 'A') {
System.out.println("B comes after A");
}
if ('E' >= 'E') {
System.out.println("E is equal to or comes after E");
}
// This code is here for demonstration purposes only...
ConferenceRegistrationAssistant assistant = new ConferenceRegistrationAssistant();
/*
Remember that there are 2 lines.
Line #1 is for A-M
Line #2 is for N-Z
*/
int lineNumber = 0;
/*
This should set lineNumber to 2 because
The last name is Zimmerman which starts with a Z.
Therefore it is between N-Z
*/
lineNumber = assistant.getLineNumberFor("Zimmerman");
/*
This method call should set lineNumber to 1, because 'A' from "Anderson" is between A-M.
*/
lineNumber = assistant.getLineNumberFor("Anderson");
/*
Likewise Charlie Brown's 'B' is between 'A' and 'M', so lineNumber should be set to 1
*/
lineNumber = assistant.getLineNumberFor("Brown");
}
}
1 Answer
Felix Sonnenholzer
14,654 PointsHi Gabriel,
you need to compare only the first letter in the String. charAt
is expecting an index, but you are giving it a comparison.
You need the comparison between the first char AND 'M'
Try it that way.
// first letter in a String is Index 0
if (lastName.charAt(0) <= 'M') {
lineNumber = 1;
} else {
// a simple if else statement should work in this case
lineNumber = 2;
}
I hope that helped.