Java program to count the occurrences of each character

Write a Java program which prints number of occurrences of each characters and also it should not print repeatedly occurrences of duplicate characters as given in the example:

Examples:

Input : geeksforgeeks
Output :
Number of Occurrence of g is:2
Number of Occurrence of e is:4
Number of Occurrence of k is:2
Number of Occurrence of s is:2
Number of Occurrence of f is:1
Number of Occurrence of o is:1
Number of Occurrence of r is:1

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

The idea is to create a count array of size 256. Traverse input string and for every character increment its count.

class NoOfOccurenceOfCharacters { 
    static final int MAX_CHAR = 256; 
  
    static void getOccuringChar(String str) 
    { 
        // Create an array of size 256 i.e. ASCII_SIZE 
        int count[] = new int[MAX_CHAR]; 
  
        int len = str.length(); 
  
        // Initialize count array index 
        for (int i = 0; i < len; i++) 
            count[str.charAt(i)]++; 
  
        // Create an array of given String size 
        char ch[] = new char[str.length()]; 
        for (int i = 0; i < len; i++) { 
            ch[i] = str.charAt(i); 
            int find = 0; 
            for (int j = 0; j <= i; j++) { 
  
                // If any matches found 
                if (str.charAt(i) == ch[j])  
                    find++;                 
            } 
  
            if (find == 1)  
                System.out.println("Number of Occurrence of " + 
                 str.charAt(i) + " is:" + count[str.charAt(i)]);             
        } 
    } 
    public static void main(String[] args) 
    { 
        Scanner sc = new Scanner(System.in); 
        String str = "geeksforgeeks"; 
        getOccuringChar(str); 
    } 
} 

Output:

Number of Occurrence of g is:2
Number of Occurrence of e is:4
Number of Occurrence of k is:2
Number of Occurrence of s is:2
Number of Occurrence of f is:1
Number of Occurrence of o is:1
Number of Occurrence of r is:1

My Personal Notes

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Bishal Kumar Dubey

Hello everyone, I am Bishal KUMAR Dubey and most importantly an idea creator I just love Programming languages and love to know new concepts everyday,every minute,every second Here to help Other GEEKS

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