Thread: Char Array Increment + 1

Hello Nuggets!
Why are you using FileReader to read from the console? In my opinion you are using way too much code for just asking the user for input.
And also, as i can see you have in your for loop

if (result < 25) {
System.out.print(result + 1);

So it will print the same int for every character of the String the user inputs if result is less than 25.
Hope i explained it right.

Originally Posted by andreas90

Hello Nuggets!
Why are you using FileReader to read from the console? In my opinion you are using way too much code for just asking the user for input.
And also, as i can see you have in your for loop

if (result < 25) {
System.out.print(result + 1);

So it will print the same int for every character of the String the user inputs if result is less than 25.
Hope i explained it right.

I'm entering in a txt file to convert. I thought this statement was supposed to sort the array, then search the binary number for the character. Thus I then did the if (result < 25), meaning if the value of the character was less than 25 in the array, it would print out the character and increment it by 1.

Arrays.sort(Alphabet);
			int result = Arrays.binarySearch(Alphabet, value);

Originally Posted by Norm

Add some println statements to print out the results of the methods you are calling so you can see what they are doing.

All it prints out is -1-1-1 for "ABC".

if (result < 25) {
								System.out.println("val" + result);

Output: val-1
val-1
val-1

	if (result == 25) {
								System.out.print(Alphabet[0]);

Output: gives an exception on line 22.

The problem is it's not searching any binary values in the input. If it did, then the first code would print out every letter in the alphabet array from A to Y.

Originally Posted by copeg

A note on your approach - it is redundant to use an array to get the next index of that array if you wish to increment a character value. characters can be cast to integers, the value of which is the ascii decimal value for that character - and those decimal values are in order with the alphabet. In other words:

char c = 'c';
char d = (char)(((int)c) + 1);//equals 'd'

No need to search an array for each character, let alone create that array in the first place. Search the internet for an ascii table to see the full range of decimal values

So i need to create that code for every letter in my array from A to Z? I want this program to input any string of letters, like "BALL" then increment each one of those characters to the next letter in the alphabet. So "BALL" would output "CBII".

int result = Arrays.binarySearch(Alphabet, value);

This code searches for a character in the Alphabet array, then assigns it a value correct? If not, can someone please explain to me what binarySearch does.

Originally Posted by Nuggets

int result = Arrays.binarySearch(Alphabet, value);

This code searches for a character in the Alphabet array, then assigns it a value correct? If not, can someone please explain to me what binarySearch does.

Take a look at here

Originally Posted by andreas90

Take a look at here

So why isn't it only returning -1 as the index for my system.out.print(result).

Originally Posted by Norm

What is the contents of the value variable you are searching for?
Use println to see.

My value variable is set to equal 0. That's all I've done with it. It gives an error when I compile without the = 0.

Originally Posted by Nuggets

So why isn't it only returning -1 as the index for my system.out.print(result).

What does it do instead?

Originally Posted by andreas90

What does it do instead?

Well, if I do system.out.print(result + 1); it will print out 0 instead of -1.

Originally Posted by Nuggets

Well, if I do system.out.print(result + 1); it will print out 0 instead of -1.

result should be -1 as you mentioned in post #16. result +1 = -1+1 = 0
Am i missing something?

This is getting frustrating. I modified char value = 0; and changed it to char value = 'C'. Now System.out.println(result); will output 2, which is the correct value in my char Alphabet array. How would I search every letter that has been entered through the program instead of just one? And, how would I convert that binary number into the letter that is in the char Alphabet array so it will output the letter instead of the number?

edit*, I forgot to add that my input is just "C".

Originally Posted by Nuggets

How would I search every letter that has been entered through the program instead of just one?

You do that with your for loop if i'm getting it right.

Originally Posted by Nuggets

And, how would I convert that binary number into the letter that is in the char Alphabet array so it will output the letter instead of the number?

edit*, I forgot to add that my input is just "C".

Check out the charAt(int) method of the String class. You can use it inside the for loop as value.