Second most repeated word in a sequence

Last Updated : 26 Mar, 2025

Given a sequence of strings, the task is to find out the second most repeated (or frequent) string in the given sequence. You may assume that no two words are the second most repeated, there will be always a single word.

Examples:

Input: ["aaa", "bbb", "ccc", "bbb", "aaa", "aaa"]
Output: bbb
Explanation: "bbb" is the second most repeated word and is repeated 2 times after "aaa" which is repeated 3 times.
Input: ["geeks", "for", "geeks", "for", "geeks", "aaa"]
Output: for
Explanation: "for" is the second most repeated word and is repeated 2 times after "geeks" which is repeated 3 times.

Table of Content

[Naive Approach] Using Nested Loops – O(n^2*k) Time and O(1) Space

We use nested loops to compare each word with the rest of the words to count its occurrences. Then, we find the second most repeated word by keeping track of the highest and second-highest counts.

C++

#include <bits/stdc++.h>
using namespace std;

string secondMaxWord(const vector<string>& words) {
    int n = words.size();
    int fMax = 0, sMax = 0;
    string sWord = "";

     for (int i = 0; i < n; i++) {
        int cnt = 0;
        for (int j = 0; j < n; j++) {
            if (words[i] == words[j]) {
                cnt++;
            }
        }

        // Track most and second most repeated words
        if (cnt > fMax) {
            sMax = fMax;
            sWord = words[i];
            fMax = cnt;
        } else if (cnt > sMax && cnt < fMax) {
            sMax = cnt;
            sWord = words[i];
        }
    }

    return sWord;
}

int main() {
    vector<string> words = {"geeks", "for", "geeks", "for", "geeks", "aaa"};
    cout << secondMaxWord(words) << endl;
    return 0;
}

Java

import java.util.*;

public class Main {

    public static String secondMaxWord(List<String> words) {
        int n = words.size();
        int fMax = 0, sMax = 0;
        String sWord = "";

        for (int i = 0; i < n; i++) {
            int cnt = 0;
            for (int j = 0; j < n; j++) {
                if (words.get(i).equals(words.get(j))) {
                    cnt++;
                }
            }

            // Track most and second most repeated words
            if (cnt > fMax) {
                sMax = fMax;
                sWord = words.get(i);
                fMax = cnt;
            } else if (cnt > sMax && cnt < fMax) {
                sMax = cnt;
                sWord = words.get(i);
            }
        }

        return sWord;
    }

    public static void main(String[] args) {
        List<String> words = Arrays.asList("geeks", "for", "geeks", "for", "geeks", "aaa");
        System.out.println(secondMaxWord(words));
    }
}

Python

def secondMaxWord(words):
    n = len(words)
    fMax, sMax = 0, 0
    sWord = ""

    for i in range(n):
        cnt = 0
        for j in range(n):
            if words[i] == words[j]:
                cnt += 1

        # Track most and second most repeated words
        if cnt > fMax:
            sMax = fMax
            sWord = words[i]
            fMax = cnt
        elif cnt > sMax and cnt < fMax:
            sMax = cnt
            sWord = words[i]

    return sWord

words = ["geeks", "for", "geeks", "for", "geeks", "aaa"]
print(secondMaxWord(words))

using System;
using System.Collections.Generic;

class Program {

    public static string secondMaxWord(List<string> words) {
        int n = words.Count;
        int fMax = 0, sMax = 0;
        string sWord = "";

        for (int i = 0; i < n; i++) {
            int cnt = 0;
            for (int j = 0; j < n; j++) {
                if (words[i] == words[j]) {
                    cnt++;
                }
            }

            // Track most and second most repeated words
            if (cnt > fMax) {
                sMax = fMax;
                sWord = words[i];
                fMax = cnt;
            } else if (cnt > sMax && cnt < fMax) {
                sMax = cnt;
                sWord = words[i];
            }
        }

        return sWord;
    }

    static void Main() {
        List<string> words = new List<string> {"geeks", "for", "geeks", "for", "geeks", "aaa"};
        Console.WriteLine(secondMaxWord(words));
    }
}

JavaScript

function secondMaxWord(words) {
    let n = words.length;
    let fMax = 0, sMax = 0;
    let sWord = "";

    for (let i = 0; i < n; i++) {
        let cnt = 0;
        for (let j = 0; j < n; j++) {
            if (words[i] === words[j]) {
                cnt++;
            }
        }

        // Track most and second most repeated words
        if (cnt > fMax) {
            sMax = fMax;
            sWord = words[i];
            fMax = cnt;
        } else if (cnt > sMax && cnt < fMax) {
            sMax = cnt;
            sWord = words[i];
        }
    }

    return sWord;
}

let words = ["geeks", "for", "geeks", "for", "geeks", "aaa"];
console.log(secondMaxWord(words));

Output

bbb

Time Complexity will be O(n²k) where n is the size of array and k is the average word length.

[Expected Approach] Using Hashing – O(n*k) Time and O(n) Space

Counting Words: We use a map (or dictionary) to store the frequency of each word.
Track Most and Second Most Frequent Words: We iterate over the map to find the word with the highest count and the second highest count.
Return Second Most Frequent Word: After finding the counts, the second most frequent word is returned.

C++

#include <bits/stdc++.h>
using namespace std;

string secondMaxWord(const vector<string>& words) {
    unordered_map<string, int> wordCount;

    for (const string& word : words) {
        wordCount[word]++;
    }

    // Find the most and second most repeated word
    int fMax = 0, sMax = 0;
    string fWord = "", sWord = "";

    for (auto& entry : wordCount) {
        if (entry.second > fMax) {
            sMax = fMax;
            sWord = fWord;
            fMax = entry.second;
            fWord = entry.first;
        } else if (entry.second > sMax && entry.second < fMax) {
            sMax = entry.second;
            sWord = entry.first;
        }
    }

    return sWord;
}

int main() {
    vector<string> words = {"aaa", "bbb", "ccc", "bbb", "aaa", "aaa"};
    cout  << secondMaxWord(words) << endl;
    return 0;
}

Java

import java.util.*;

public class Main {

    public static String secondMaxWord(List<String> words) {
        Map<String, Integer> wordCount = new HashMap<>();

        for (String word : words) {
            wordCount.put(word, wordCount.getOrDefault(word, 0) + 1);
        }

        // Find the most and second most repeated word
        int fMax = 0, sMax = 0;
        String fWord = "", sWord = "";

        for (Map.Entry<String, Integer> entry : wordCount.entrySet()) {
            if (entry.getValue() > fMax) {
                sMax = fMax;
                sWord = fWord;
                fMax = entry.getValue();
                fWord = entry.getKey();
            } else if (entry.getValue() > sMax && entry.getValue() < fMax) {
                sMax = entry.getValue();
                sWord = entry.getKey();
            }
        }

        return sWord;
    }

    public static void main(String[] args) {
        List<String> words = Arrays.asList("aaa", "bbb", "ccc", "bbb", "aaa", "aaa");
        System.out.println(secondMaxWord(words)); 
    }
}

Python

from collections import Counter

def secondMaxWord(words):
    
    wordCount = Counter(words)

    # Find the most and second most repeated word
    fMax, sMax = 0, 0
    fWord, sWord = "", ""

    for word, count in wordCount.items():
        if count > fMax:
            sMax = fMax
            sWord = fWord
            fMax = count
            fWord = word
        elif count > sMax and count < fMax:
            sMax = count
            sWord = word

    return sWord


words = ["aaa", "bbb", "ccc", "bbb", "aaa", "aaa"]
print(secondMaxWord(words))

using System;
using System.Collections.Generic;

class Program {

    public static string secondMaxWord(List<string> words) {
        var wordCount = new Dictionary<string, int>();

        foreach (var word in words) {
            if (wordCount.ContainsKey(word))
                wordCount[word]++;
            else
                wordCount[word] = 1;
        }

        // Find the most and second most repeated word
        int fMax = 0, sMax = 0;
        string fWord = "", sWord = "";

        foreach (var entry in wordCount) {
            if (entry.Value > fMax) {
                sMax = fMax;
                sWord = fWord;
                fMax = entry.Value;
                fWord = entry.Key;
            } else if (entry.Value > sMax && entry.Value < fMax) {
                sMax = entry.Value;
                sWord = entry.Key;
            }
        }

        return sWord;
    }

    static void Main() {
        List<string> words = new List<string> { "aaa", "bbb", "ccc", "bbb", "aaa", "aaa" };
        Console.WriteLine(secondMaxWord(words));  
    }
}

JavaScript

function secondMaxWord(words) {
    let wordCount = {};

    for (let word of words) {
        wordCount[word] = (wordCount[word] || 0) + 1;
    }

    // Find the most and second most repeated word
    let fMax = 0, sMax = 0;
    let fWord = "", sWord = "";

    for (let word in wordCount) {
        if (wordCount[word] > fMax) {
            sMax = fMax;
            sWord = fWord;
            fMax = wordCount[word];
            fWord = word;
        } else if (wordCount[word] > sMax && wordCount[word] < fMax) {
            sMax = wordCount[word];
            sWord = word;
        }
    }

    return sWord;
}

let words = ["aaa", "bbb", "ccc", "bbb", "aaa", "aaa"];
console.log(secondMaxWord(words));