Count occurrences of a word in string

You are given a string and a word your task is that count the number of occurrences of the given word in the string and print the number of occurrences of the word. 

Examples:

Input : string = "GeeksforGeeks A computer science portal for geeks"
word = "portal"
Output : Occurrences of Word = 1 Time

Input : string = "GeeksforGeeks A computer science portal for geeks"
word = "technical" 
Output : Occurrences of Word = 0 Time

Approach:

• First, we split the string by spaces in a
• Then, take a variable count = 0 and in every true condition we increment the count by 1
• Now run a loop at 0 to length of string and check if our string is equal to the word
• if condition is true then we increment the value of count by 1 and in the end, we print the value of count.

Below is the implementation of the above approach : 

C

// C program to count the number
// of occurrence of a word in
// the given string
#include <stdio.h>
#include <string.h>

int countOccurrences(char *str, char *word)
{
    char *p;

    // split the string by spaces in a
    char *a[300];
      int index=0;

    p = strtok(str, " ");
    while (p != NULL)
    {
        a[index++]=(p);
        p = strtok(NULL, " ");
    }

    // search for pattern in a
    int c = 0;
    for (int i = 0; i < index; i++)
        // if match found increase count
        if (strcmp(word , a[i])==0){
            c++;
        }
    return c;
}

// Driver code
int main()
{
    char str[] = "GeeksforGeeks A computer science portal for geeks ";
    char word[] = "portal";
    printf("%d",countOccurrences(str, word));
    return 0;
}

C++

// C++ program to count the number
// of occurrence of a word in
// the given string
#include <bits/stdc++.h>
using namespace std;

int countOccurrences(char *str,
                    string word)
{
    char *p;

    // split the string by spaces in a
    vector<string> a;

    p = strtok(str, " ");
    while (p != NULL)
    {
        a.push_back(p);
        p = strtok(NULL, " ");
    }

    // search for pattern in a
    int c = 0;
    for (int i = 0; i < a.size(); i++)

        // if match found increase count
        if (word == a[i])
            c++;
    return c;
}

// Driver code
int main()
{
    char str[] = "GeeksforGeeks A computer science portal for geeks ";
    string word = "portal";
    cout << countOccurrences(str, word);
    return 0;
}

// This code is contributed by
// sanjeev2552

Java

// Java program to count the number
// of occurrence of a word in
// the given string
import java.io.*;

class GFG {

static int countOccurrences(String str, String word)
{
    // split the string by spaces in a
    String a[] = str.split(" ");

    // search for pattern in a
    int count = 0;
    for (int i = 0; i < a.length; i++)
    {
    // if match found increase count
    if (word.equals(a[i]))
        count++;
    }

    return count;
}

// Driver code
public static void main(String args[])
{
    String str = "GeeksforGeeks A computer science portal for geeks ";
    String word = "portal";
    System.out.println(countOccurrences(str, word));
}
}

/*This code is contributed by Nikita Tiwari.*/

Python 3

# Python program to count the number of occurrence
# of a word in the given string

def countOccurrences(str, word):

    # split the string by spaces in a
    a = str.split(" ")

    # search for pattern in a
    count = 0
    for i in range(0, len(a)):

        # if match found increase count
        if (word == a[i]):
           count = count + 1

    return count

# Driver code
str ="GeeksforGeeks A computer science portal for geeks  "
word ="portal"
print(countOccurrences(str, word))

C#

// C# program to count the number
// of occurrence of a word in
// the given string
using System;

class GFG
{
static int countOccurrences(string str,
                           string word)
{
    // split the string by spaces
    string[] a = str.Split(' ');

    // search for pattern in string
    int count = 0;
    for (int i = 0; i < a.Length; i++)
    {

    // if match found increase count
    if (word.Equals(a[i]))
        count++;
    }

    return count;
}

// Driver code
public static void Main()
{
    string str = "GeeksforGeeks A computer science portal for geeks ";
    string word = "portal";
    Console.Write(countOccurrences(str, word));
}
}

// This code is contributed
// by ChitraNayal

PHP

<?php
// PHP program to count the number
// of occurrence of a word in
// the given string

function countOccurrences($str, $word)
{
    // split the string by spaces
    $a = explode(" ", $str);

    // search for pattern in string
    $count = 0;
    for ($i = 0; $i < sizeof($a); $i++)
    {

    // if match found increase count
    if ($word == $a[$i])
        $count++;
    }

    return $count;
}

// Driver code
$str = "GeeksforGeeks A computer science portal for geeks ";
$word = "portal";
echo (countOccurrences($str, $word));

// This code is contributed
// by ChitraNayal
?>

Javascript

<script>

// Javascript program to count the number
// of occurrence of a word in
// the given string

    function countOccurrences(str,word)
    {
        // split the string by spaces in a
    let a = str.split(" ");

    // search for pattern in a
    let count = 0;
    for (let i = 0; i < a.length; i++)
    {
    // if match found increase count
    if (word==(a[i]))
        count++;
    }

    return count;
    }
    // Driver code
    let str = "GeeksforGeeks A computer
    science portal for geeks ";
    let word = "portal";
    document.write(countOccurrences(str, word));


    // This code is contributed by avanitrachhadiya2155

</script>

Output

1

Time Complexity: O(n)
Auxiliary Space: O(n)

Method #2: Using Count() function in python:

• First, we split the string by spaces and store in list.
• We use count() to find count of that word in list.

Below is the implementation:

Python3

# Python program to count the number of occurrence
# of a word in the given string
def countOccurrences(str, word):

    wordslist = list(str.split())
    return wordslist.count(word)


# Driver code
str = "GeeksforGeeks A computer science portal for geeks  "
word = "portal"
print(countOccurrences(str, word))

# This code is contributed by vikkycirus

C++

// C++ program to count the number of occurrence
// of a word in the given string
#include <bits/stdc++.h>
using namespace std;

int countOccurrences(string str, string word)
{
    // Split the string into words
    stringstream ss(str);
    string token;
    vector<string> wordslist;

    while (ss >> token) {
        wordslist.push_back(token);
    }

    // Count the number of occurrences of the given word
    int count = 0;
    for (int i = 0; i < wordslist.size(); i++) {
        if (wordslist[i] == word) {
            count++;
        }
    }

    return count;
}

// Driver code
int main()
{
    string str = "GeeksforGeeks A computer science portal "
                 "for geeks";
    string word = "portal";
    cout << countOccurrences(str, word);
    return 0;
}

Output

1

Time Complexity: O(n)
Auxiliary Space: O(n)

Reference: split function python