Checking if a sentence is a pangram or not

Royalty

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.

7 Replies

Know the answer? Post it — somebody with the same question will find it here.

Hiren Joshi15y ago
You are right,I am new ,I have no professional experience .I will try to make it faster than the previous one.Thank you..
Vulpes15y ago
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 < 26) return false;
bool[] isUsed = new bool[26];
int total = 0;

foreach(char c in s)
{
if (c >= 'a' && c <= 'z')
{
int index = c - 97;
if(!isUsed[index])
{
isUsed[index] = true;
total++;
}
}
}

return total == 26;
}
}

Doubtless there will be even faster methods than this.
Hiren Joshi15y ago
how abt dis?
Hiren Joshi15y ago
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 < chararray.Length; i++)
{
if(!str.Contains(chararray[i]))
{
//Console.WriteLine(chararray[i]);
pangram=pangram+chararray[i];
}
}
return pangram;
}
}
}
Vulpes15y ago
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.
Royalty15y ago
Oh...so I'm not supposed to have that for loop inside another one?
Vulpes15y ago
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.