Pangram Checking

Problem Statement - link #

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

Your Task: You need to complete the function checkPangram() that takes a string as a parameter and returns true if the string is a pangram, else it returns false.

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(Number of distinct characters)

Examples #

Example 1:

Input:
S = Bawds jog, flick quartz, vex nymph
Output: 1
Explantion: In the given input, there
are all the letters of the English
alphabet. Hence, the output is 1.

Example 2:

Input:
S = sdfs
Output: 0
Explantion: In the given input, there
aren't all the letters present in the
English alphabet. Hence, the output
is 0.

Constraints #

• 1 <= length of the string <= 10^4

Solutions #

class Solution{
    public:
    //Function to check if a string is Pangram or not.
    bool checkPangram (string &str) {
        // your code here
        unordered_set<char> us;
        for(int i=0; i<str.size(); i++){
            if(isalpha(str[i]))
                us.insert(tolower(str[i]));
        }
        return us.size()==26;
    }
};