C# Sharp Exercises: Check if a string has all unique characters

Last update on December 20 2024 12:44:29 (UTC/GMT +8 hours)

Write a C# Sharp program to check whether all characters in a given string are unique. If all the characters are distinct, return “There is no similarity between any of the characters!” otherwise if not unique, then:

Display a message stating this.
Display the duplicated character.
It is only necessary to display the first non-unique character.
Display where "both" duplicated characters appears in the string.
All of the above messages can be incorporated into a single message.

Sample Solution:

C# Sharp Code:

using System;
using System.Linq;

namespace exercises
{
    class Program
    {
        static void Main(string[] args)
        {
            // Define an array of strings containing various test cases
            string[] text = { "", ".", "cppCPP", "PQR RQP", "The quick brown fox jumps over the lazy dog.", "C Sharp" };

            // Iterate through each string in the 'text' array
            foreach (string word in text)
            {
                // Display the current string, its length, and the characters with their positions having similarities
                Console.WriteLine($"\n\"{word}\" (Length {word.Length}) " +
                    string.Join(", ",
                        // Select each character along with its index in the string
                        word.Select((ch, i) => new { ch, i })
                        // Group characters by their value and filter groups with more than one occurrence
                        .GroupBy(tm => tm.ch).Where(gr => gr.Count() > 1)
                        // Select groups and construct strings showing characters with their positions
                        .Select(gr => $"'{gr.Key}'[{string.Join(", ", gr.Select(tm => tm.i))}]")
                        // If no similarity between characters found, display a default message
                        .DefaultIfEmpty("There is no similarity between any of the characters!")));
            }
        }
    }
}

Sample Output:

"" (Length 0) There is no similarity between any of the characters!
"." (Length 1) There is no similarity between any of the characters!
"cppCPP" (Length 6) 'p'[1, 2], 'P'[4, 5]
"PQR RQP" (Length 7) 'P'[0, 6], 'Q'[1, 5], 'R'[2, 4]
"The quick brown fox jumps over the lazy dog." (Length 44) 'h'[1, 32], 'e'[2, 28, 33], ' '[3, 9, 15, 19, 25, 30, 34, 39], 'u'[5, 21], 'r'[11, 29], 'o'[12, 17, 26, 41]
"C Sharp" (Length 7) There is no similarity between any of the characters!

Flowchart :

C# Sharp Code Editor:

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