Check if the Sentence Is Pangram

check一个string是不是包含所有的26个字母

class Solution {
    public boolean checkIfPangram(String sentence) {
        int[] count = new int[26];
        for(char c : sentence.toCharArray()){
            count[c - 'a']++;
        }
        for(int n : count){
            if(n == 0)
                return false;
        }
        return true;
    }
}