Count the occurrences of a letter in a string

Question

I am trying to write a for loop in Java that will count the occurrences of a letter in a string. The user will enter the letter to count and the string in which to search. This

Answer 1

try the indexOf() method. it should work

Answer 2

1. You need to know the char you wanna search. You can use char charToSearch = letter.toCharArray()[0];
2. Define a variable, such as count to count the occurrences of a letter in a given string.
3. Loop the string and compare each char, if the char is equal to the char to search, then count++;

Example--->

int count = 0;
char charToSearch = letter.toCharArray()[0];
for (int i = 0; i < sentence.length(); i++) {
    if (sentence.charAt(i) ==  charToSearch) {
        count++;
    }
}

System.out.printf("Occurrences of a %s in %s is %d", letter, sentence, count);

Answer 3

Hope this will helpful to you.

import java.util.Scanner;

public class CountCharacters {
    public static void main(String[] args) {

        Scanner in = new Scanner(System.in);

        System.out.println("Enter the string to search");
        String sentence = in.nextLine();

        System.out.println("Enter a character for which to search");
        String letter = in.next();

        int noOfOccurance = 0;

        for (int i = 0; i < sentence.length(); i++) {
            char dh=letter.charAt(0);
            char ch = sentence.charAt(i);
            if (dh==ch) {
               noOfOccurance++;
            }
       }
       System.out.print(noOfOccurance);
    }
}

Sample Input Output:

Enter the string to search
how are you
Enter a character for which to search
o
No of Occurances : 2

Answer 4

No need to loop:

    String sentence = "abcabcabcd";
    String letter = "b";
    int numOfOccurences = sentence.length() - 
                          sentence.replaceAll(letter, "").length();
    System.out.println("numOfOccurences = "+numOfOccurences);

OUTPUT:

numOfOccurences = 3