C# Program to Find the Frequency of “is” Word in a String


This is a C# Program to find the frequency of the word ʺisʺ in a given Sentence.

Problem Description

This C# Program Finds the Frequency of the Word ʺisʺ in a given Sentence.

Program/Source Code

Here the frequency of ‘is’ in the given string is found.

Program/Source Code

Here is source code of the C# Program to Find the Frequency of the Word ʺisʺ in a given Sentence. The C# program is successfully compiled and executed with Microsoft Visual Studio. The program output is also shown below.

 * C# Program to Find the Frequency of the Word ʺisʺ in a given Sentence
using System;
class program
    public static void Main()
        string s1;
        Console.WriteLine("Enter the String : ");
        s1 = Console.ReadLine();
        Console.WriteLine(counting.CountStringOccurrences(s1, "is"));
public static class counting
    public static int CountStringOccurrences(string text, string pattern)
        int count = 0;
        int i = 0;
        while ((i = text.IndexOf(pattern, i)) != -1)
            i += pattern.Length;
        return count;
Program Explanation

In this C# program, we are reading the string using ‘s1’ variable. The CountStringOccurrences() function is used to find the frequency of the word “is” in a given sentence from the counting variable.


While loop is used to check the value of IndexOf() function is not equal to -1. If the condition is true then execute the iteration of the loop. Compute the addition of the value of ‘i’ variable with value of ‘pattern.length’ variable and increment the value of ‘count’ variable. Print the frequency of the word “is” in a sentence.

Runtime Test Cases
Enter the String :
Rose is a Flower

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Manish Bhojasia, a technology veteran with 20+ years @ Cisco & Wipro, is Founder and CTO at Sanfoundry. He lives in Bangalore, and focuses on development of Linux Kernel, SAN Technologies, Advanced C, Data Structures & Alogrithms. Stay connected with him at LinkedIn.

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