Simple solution, no set/map
```\nclass Solution {\n    public boolean checkIfPangram(String sentence) {\n        int seen = 0;\n        for(char c : sentence.toCharArray()) {\n            
```\nclass Solution {\n    public boolean checkIfPangram(String sentence) {\n        int seen = 0;\n        for(char c : sentence.toCharArray()) {\n            int ci = c - \'a\';\n            seen = seen | (1 << ci);\n        }\n        return seen == ((1 << 26) - 1);\n    }\n}
[]