Program to find Smallest and Largest Word in a String

Given a string, find the minimum and the maximum length words in it. 

Examples:

Input : "This is a test string"
Output : Minimum length word: a
         Maximum length word: string

Input : "GeeksforGeeks A computer Science portal for Geeks"
Output : Minimum length word: A
         Maximum length word: GeeksforGeeks

Method 1: The idea is to keep a starting index si and an ending index ei. 

• si points to the starting of a new word and we traverse the string using ei.
• Whenever a space or ‘\0’ character is encountered,we compute the length of the current word using (ei – si) and compare it with the minimum and the maximum length so far. 
  • If it is less, update the min_length and the min_start_index( which points to the starting of the minimum length word).
  • If it is greater, update the max_length and the max_start_index( which points to the starting of the maximum length word).
• Finally, update minWord and maxWord which are output strings that have been sent by reference with the substrings starting at min_start_index and max_start_index of length min_length and max_length respectively.

Below is the implementation of the above approach:

C++

// CPP Program to find Smallest and
// Largest Word in a String
#include<iostream>
#include<cstring>
using namespace std;

void minMaxLengthWords(string input, string &minWord, string &maxWord)
{
    // minWord and maxWord are received by reference
    // and not by value
    // will be used to store and return output
    int len = input.length();
    int si = 0, ei = 0;


    int min_length = len, min_start_index = 0, max_length = 0, max_start_index = 0;

    // Loop while input string is not empty
    while (ei <= len)
    {
        if (ei < len && input[ei] != ' ')
            ei++;

        else
        {
            // end of a word
            // find curr word length
            int curr_length = ei - si;

            if (curr_length < min_length)
            {
                min_length = curr_length;
                min_start_index = si;
            }

            if (curr_length > max_length)
            {
                max_length = curr_length;
                max_start_index = si;
            }
            ei++;
            si = ei;
        }
    }

    // store minimum and maximum length words
    minWord = input.substr(min_start_index, min_length);
    maxWord = input.substr(max_start_index, max_length);
}

// Driver code
int main()
{
    string a = "GeeksforGeeks A Computer Science portal for Geeks";
    string minWord, maxWord;
    minMaxLengthWords(a, minWord, maxWord);

    // to take input in string use getline(cin, a);
    cout << "Minimum length word: "
        << minWord << endl
        << "Maximum length word: "
        << maxWord << endl;
}

Java

// Java Program to find Smallest and
// Largest Word in a String
import java.io.*;
class GFG
{

    static String minWord = "", maxWord = "";

    static void minMaxLengthWords(String input)
    {
          input=input.trim();//Triming any space before the String else space at start would be consider as smallest word
        // minWord and maxWord are received by reference
        // and not by value
        // will be used to store and return output

        int len = input.length();
        int si = 0, ei = 0;
        int min_length = len, min_start_index = 0,
              max_length = 0, max_start_index = 0;

        // Loop while input string is not empty
        while (ei <= len)
        {
            if (ei < len && input.charAt(ei) != ' ')
            {
                ei++;
            }
            else
            {
                // end of a word
                // find curr word length
                int curr_length = ei - si;

                if (curr_length < min_length)
                {
                    min_length = curr_length;
                    min_start_index = si;
                }

                if (curr_length > max_length)
                {
                    max_length = curr_length;
                    max_start_index = si;
                }
                ei++;
                si = ei;
            }
        }

        // store minimum and maximum length words
        minWord = input.substring(min_start_index, min_start_index + min_length);
        maxWord = input.substring(max_start_index, max_start_index+max_length);//Earlier  code was not working if the largests word is inbetween String
    }

    // Driver code
    public static void main(String[] args)
    {
        String a = "GeeksforGeeks A Computer Science portal for Geeks";

        minMaxLengthWords(a);

        // to take input in string use getline(cin, a);
        System.out.print("Minimum length word: "
                + minWord
                + "\nMaximum length word: "
                + maxWord);
    }
}

// This code contributed by Rajput-Ji

Python 3

# Python3 program to find Smallest and
# Largest Word in a String

# defining the method to find the longest
# word and the shortest word
def minMaxLengthWords(inp):
    length = len(inp)
    si = ei = 0
    min_length = length
    min_start_index = max_length = max_start_index = 0

    # loop to find the length and stating index
    # of both longest and shortest words
    while ei <= length:
        if (ei < length) and (inp[ei] != " "):
            ei += 1
        else:
            curr_length = ei - si

            # condition checking for the shortest word
            if curr_length < min_length:
                min_length = curr_length
                min_start_index = si

            # condition for the longest word
            if curr_length > max_length:
                max_length = curr_length
                max_start_index = si
            ei += 1
            si = ei

    # extracting the shortest word using
    # it's starting index and length
    minWord = inp[min_start_index :
                  min_start_index + min_length]

    # extracting the longest word using
    # it's starting index and length
    maxWord = inp[max_start_index : max_length]

    # printing the final result
    print("Minimum length word: ", minWord)
    print ("Maximum length word: ", maxWord)

# Driver Code

# Using this string to test our code
a = "GeeksforGeeks A Computer Science portal for Geeks"
minMaxLengthWords(a)

# This code is contributed by Animesh_Gupta

C#

// C# Program to find Smallest and
// Largest Word in a String
using System;

class GFG
{

    static String minWord = "", maxWord = "";

    static void minMaxLengthWords(String input)
    {
        // minWord and maxWord are received by reference
        // and not by value
        // will be used to store and return output
        int len = input.Length;
        int si = 0, ei = 0;
        int min_length = len, min_start_index = 0,
            max_length = 0, max_start_index = 0;

        // Loop while input string is not empty
        while (ei <= len)
        {
            if (ei < len && input[ei] != ' ')
            {
                ei++;
            }
            else
            {
                // end of a word
                // find curr word length
                int curr_length = ei - si;

                if (curr_length < min_length)
                {
                    min_length = curr_length;
                    min_start_index = si;
                }

                if (curr_length > max_length)
                {
                    max_length = curr_length;
                    max_start_index = si;
                }
                ei++;
                si = ei;
            }
        }

        // store minimum and maximum length words
        minWord = input.Substring(min_start_index, min_length);
        maxWord = input.Substring(max_start_index, max_length);
    }

    // Driver code
    public static void Main(String[] args)
    {
        String a = "GeeksforGeeks A Computer Science portal for Geeks";

        minMaxLengthWords(a);

        // to take input in string use getline(cin, a);
        Console.Write("Minimum length word: "
                + minWord
                + "\nMaximum length word: "
                + maxWord);
    }
}

// This code has been contributed by 29AjayKumar

Javascript

<script>

// JavaScript Program to find Smallest and
// Largest Word in a String

let minWord = "";
let maxWord = "";

function minMaxLengthWords(input)
{
    // minWord and maxWord are received by reference
    // and not by value
    // will be used to store and return output
    let len = input.length;
    let si = 0, ei = 0;
    let min_length = len;
    let min_start_index = 0;
    let max_length = 0;
    let max_start_index = 0;

    // Loop while input string is not empty
    while (ei <= len)
    {
        if (ei < len && input[ei] != ' ')
        {
            ei++;
        }
        else
        {
            // end of a word
            // find curr word length
            let curr_length = ei - si;

            if (curr_length < min_length)
            {
                min_length = curr_length;
                min_start_index = si;
            }

            if (curr_length > max_length)
            {
                max_length = curr_length;
                max_start_index = si;
            }
            ei++;
            si = ei;
        }
    }

    // store minimum and maximum length words
    minWord =
    input.substring(min_start_index,min_start_index + min_length);

    maxWord =
    input.substring(max_start_index, max_length);

}

// Driver code

let a = "GeeksforGeeks A Computer Science portal for Geeks";

minMaxLengthWords(a);

// to take input in string use getline(cin, a);
document.write("Minimum length word: "
        + minWord+"<br>"
        + "Maximum length word:  "
        + maxWord);

</script>

Output

Minimum length word: A
Maximum length word: GeeksforGeeks

Time Complexity: O(n), where n is the length of string.
Auxiliary Space: O(n), where n is the length of string. This is because when string is passed in the function it creates a copy of itself in stack.