Checking if a sentence is a pangram or not

Question

Hi all

I have a piece of psuedocade here and it is supposed to check if a sentence entered by a user is a pangram or not. Please have a look at it.

string sentence;

bool pangram ßtrue;

ARRAY: characterArray of [26] char ß {'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};

ARRAY: sCharacterArray of char ß { '.', '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '_', '-', '=', '<', '|', '/', '>' };

Input the sentence

for (int i ß0;i <characterArray.Length; i++)

IF (!sentence.ToLower().Contains(characterArray[i]))

pangram ß false

ELSE

{

for(int x = 0; x < sCharArray.Length; x++)

{

if(sentence.Contains(sCharArray[x]))

{

pangram=false;

}

else

{

pangram=true;

}

ENDIF

ENDFOR

if ( pangram ßtrue)

Display ('pangram');

else

Display ('not a pangram');

ENDIF

//end program

Feedback will be appreciated. Thank you.

Hiren Joshi · Answer

how abt dis?

Hiren Joshi · Answer

You are rightI am new I have no professional experience .I will try to make it faster than the previous one.Thank you..

Vulpes · Answer

Well it works (it's a pangram if pangram.Length == 0) but due to the use of the Contains method and the string concatenations it's about 18 times slower than the standard algorithm for working out whether a given sentence is a pangram or not: using System; class Pangram { static void Main() { Console.Write(Enter sentence to test : ); bool b = IsPangram(Console.ReadLine()); Console.WriteLine(b); Console.ReadKey(); } static bool IsPangram(string s) { s = s.ToLower(); if (s.Length bool[] isUsed = new bool[26]; int total = 0; foreach(char c in s) { if (c >= 'a' && c { int index = c - 97; if(!isUsed[index]) { isUsed[index] = true; total++; } } } return total == 26; } } Doubtless there will be even faster methods than this.

Hiren Joshi · Answer

using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace pangrams { class Pangrams { static void Main() { Console.WriteLine(Enter String to be checked...); string str = Console.ReadLine(); string result= pangrams.Get_pangram.GP(str); Console.WriteLine(Pangram string is this: {0} result); } } class Get_pangram { public static string GP(string str) {string pangram=null; int i; char[] chararray ={'a' 'b' 'c' 'd' 'e' 'f' 'g' 'h' 'i' 'j' 'k' 'l' 'm' 'n' 'o' 'p' 'q' 'r' 's' 't' 'u' 'v' 'w' 'x' 'y' 'z'}; for (i = 0; i { if(!str.Contains(chararray[i])) { //Console.WriteLine(chararray[i]); pangram=pangram+chararray[i]; } } return pangram; } } }

Vulpes · Answer

It would be more efficient if you didn't. The only situation where the pseudocode as it stands would be superior is if the sentence didn't contain 'a' in which case the code would never check for excluded characters. However in a sentence of any length this is unlikely as 'a' is of course a common letter. If it does contain an 'a' then the code will check for excluded characters at least once and probably multiple times in a sentence of any length.

Royalty · Answer

Oh...so I'm not supposed to have that for loop inside another one?

Vulpes · Answer

Well the pseudocode works but not in a particularly efficient way. This is because it is checking multiple times for 'excluded' characters. It would be better just to check once to see if the sentence includes any excluded characters and if it does then it's definitely not a pangram. Otherwise you can then check to see whether the sentence contains all 26 letters of the alphabet at least once.