How to read a letter instead of a character from a given sentences

May I know how to do with the String to read a letter from a given sentences?
I can do it only with just read 20 character from a given senteces.

Code:

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sentence.substring(0,21);

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But, how do I do with reading a letter?
I try with substring but cannot work
below is the try code.

Code:

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sentence.substring(0,"  ");

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I put this " " to represent space, but it cannot take this parameter, what should I use instead?

Thank you for the help.

By letter do you mean a word? Do you want to split a string using spaces?
If that is the case then read the API specs for the String.split method.

sentence.split(" "); //splits at spaces

Ur question is not clear.

But,What I understood is that u want to read character know? Then u can go for this below method

charAt
public char charAt(int index)Returns the character at the specified index. An index ranges from 0 to length() - 1. The first character of the sequence is at index 0, the next at index 1, and so on, as for array indexing.

Specified by:
charAt in interface CharSequence
Parameters:
index - the index of the character.
Returns:
the character at the specified index of this string. The first character is at index 0.
Throws:
IndexOutOfBoundsException - if the index argument is negative or not less than the length of this string.

The question is ask me to print a string composed of first letter of the sentence, followed by printing first five characters of the sentence.
I can do with printing first five characters of sentence by using the code sentence.substring(0,6).
However, I do not know how to do with the first letter of the sentence.
I try the guide from other two replier, but I can't do it
sentence.split(" ");
is an error.
Still seeking for help.

Could u please explain with example input and output u want.........Still not clear

Mickey Mouse is cute.
//to print first 5 characters of this sentence.
sentence.substring(0,6)
output: Micke

//to print first letter of this sentence.
output: Mickey
how should I do this?
using this sentence.split(" "); I cannot get any output come out.
How should I correct this code?

You should have done as suggested above and actually read the API specs for the String.split method.

Do you know what it does and what it returns if you do sentence.split(" ")?

P.S Mickey Mouse is not cute.

Run this code below for knowing how split works.

It just split the line by whatever delimiter u are giving and stores into array.


Run this code below

Code:

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class Test
{
        public static void main(String[] args)
        {
                String s = "Mickey Mouse is cute";
                String outputArr[] = s.split(" ");

                for(int i=0; i < outputArr.length; i++)
                System.out.println(outputArr[i]);
        }
}

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