Pangram Checking - GeeksforGeeks

Given a string check if it is Pangram or not. A pangram is a sentence containing every letter in the English Alphabet.

Examples : The quick brown fox jumps over the lazy dog ” is a Pangram [Contains all the characters from ‘a’ to ‘z’]
“The quick brown fox jumps over the dog” is not a Pangram [Doesn’t contains all the characters from ‘a’ to ‘z’, as ‘l’, ‘z’, ‘y’ are missing]

Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

We create a mark[] array of Boolean type. We iterate through all the characters of our string and whenever we see a character we mark it. Lowercase and Uppercase are considered the same. So ‘A’ and ‘a’ are marked in index 0 and similarly ‘Z’ and ‘z’ are marked in index 25.

After iterating through all the characters we check whether all the characters are marked or not. If not then return false as this is not a pangram else return true.

C++

// A C++ Program to check if the given 
// string is a pangram or not 
#include <bits/stdc++.h> 
using namespace std; 
  
// Returns true if the string is pangram else false 
bool checkPangram(string& str) 
{ 
    // Create a hash table to mark the characters 
    // present in the string 
    vector<bool> mark(26, false); 
  
    // For indexing in mark[] 
    int index; 
  
    // Traverse all characters 
    for (int i = 0; i < str.length(); i++) { 
  
        // If uppercase character, subtract 'A' 
        // to find index. 
        if ('A' <= str[i] && str[i] <= 'Z') 
            index = str[i] - 'A'; 
  
        // If lowercase character, subtract 'a' 
        // to find index. 
        else if ('a' <= str[i] && str[i] <= 'z') 
            index = str[i] - 'a'; 
  
        // If this character is other than english 
        // lowercase and uppercase characters. 
        else
            continue; 
  
        mark[index] = true; 
    } 
  
    // Return false if any character is unmarked 
    for (int i = 0; i <= 25; i++) 
        if (mark[i] == false) 
            return (false); 
  
    // If all characters were present 
    return (true); 
} 
  
// Driver Program to test above functions 
int main() 
{ 
    string str = "The quick brown fox jumps over the"
                 " lazy dog"; 
  
    if (checkPangram(str) == true) 
        printf(" %s is a pangram", str.c_str()); 
    else
        printf(" %s is not a pangram", str.c_str()); 
  
    return (0); 
} 

Java

// Java Program to illustrate Pangram 
class GFG { 
  
    // Returns true if the string 
    // is pangram else false 
    public static boolean checkPangram(String str) 
    { 
        // Create a hash table to mark the 
        // characters present in the string 
        // By default all the elements of 
        // mark would be false. 
        boolean[] mark = new boolean[26]; 
  
        // For indexing in mark[] 
        int index = 0; 
  
        // Traverse all characters 
        for (int i = 0; i < str.length(); i++) { 
            // If uppercase character, subtract 'A' 
            // to find index. 
            if ('A' <= str.charAt(i) && str.charAt(i) <= 'Z') 
                index = str.charAt(i) - 'A'; 
  
            // If lowercase character, subtract 'a' 
            // to find index. 
            else if ('a' <= str.charAt(i) && str.charAt(i) <= 'z') 
  
                index = str.charAt(i) - 'a'; 
  
            // If this character is other than english 
            // lowercase and uppercase characters. 
            else
                continue; 
            mark[index] = true; 
        } 
  
        // Return false if any character is unmarked 
        for (int i = 0; i <= 25; i++) 
            if (mark[i] == false) 
                return (false); 
  
        // If all characters were present 
        return (true); 
    } 
  
    // Driver Code 
    public static void main(String[] args) 
    { 
        String str = "The quick brown fox jumps over the lazy dog"; 
  
        if (checkPangram(str) == true) 
            System.out.print(str + " is a pangram."); 
        else
            System.out.print(str + " is not a pangram."); 
    } 
} 

Python

# A Python Program to check if the given 
# string is a pangram or not 
  
def checkPangram(s): 
    List = [] 
    # create list of 26 charecters and set false each entry 
    for i in range(26): 
        List.append(False) 
          
    # converting the sentence to lowercase and iterating 
    # over the sentence  
    for c in s.lower():  
        if not c == " ": 
  
            # make the corresponding entry True 
            List[ord(c) -ord('a')]= True 
              
    # check if any charecter is missing then return False 
    for ch in List: 
        if ch == False: 
            return False
    return True
  
# Driver Program to test above functions 
sentence = "The quick brown fox jumps over the little lazy dog"
  
if (checkPangram(sentence)): 
    print '"'+sentence+'"'
    print "is a pangram"
else: 
    print '"'+sentence+'"'
    print "is not a pangram"
  
# This code is contributed by Danish Mushtaq   

C#

// C# Program to illustrate Pangram 
using System; 
class GFG { 
  
    // Returns true if the string 
    // is pangram else false 
    public static bool checkPangram(string str) 
    { 
  
        // Create a hash table to mark the 
        // characters present in the string 
        // By default all the elements of 
        // mark would be false. 
        bool[] mark = new bool[26]; 
  
        // For indexing in mark[] 
        int index = 0; 
  
        // Traverse all characters 
        for (int i = 0; i < str.Length; i++) { 
            // If uppercase character, subtract 'A' 
            // to find index. 
            if ('A' <= str[i] && str[i] <= 'Z') 
                index = str[i] - 'A'; 
  
            // If lowercase character, 
            // subtract 'a' to find 
            // index. 
            else if ('a' <= str[i] && str[i] <= 'z') 
                index = str[i] - 'a'; 
  
            // If this character is other than english 
            // lowercase and uppercase characters. 
            else
                continue; 
  
            mark[index] = true; 
        } 
  
        // Return false if any 
        // character is unmarked 
        for (int i = 0; i <= 25; i++) 
            if (mark[i] == false) 
                return (false); 
  
        // If all characters 
        // were present 
        return (true); 
    } 
  
    // Driver Code 
    public static void Main() 
    { 
        string str = "The quick brown fox jumps over the lazy dog"; 
  
        if (checkPangram(str) == true) 
            Console.WriteLine(str + " is a pangram."); 
        else
            Console.WriteLine(str + " is not a pangram."); 
    } 
} 
  
// This code is contributed by nitin mittal. 

Output :

 "The quick brown fox jumps over the lazy dog"
 is a pangram

Time Complexity: O(n), where n is the length of our string
Auxiliary Space – O(1).

This article is contributed by Rachit Belwariar. If you like GeeksforGeeks and would like to contribute, you can also write an article and mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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Recommended: Please solve it on “PRACTICE ” first, before moving on to the solution.

C++

Java

Python

C#

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