Check Pangram

Given a string s, return true if it is a pangram and false otherwise. A pangram contains every English letter from a through z at least once. Matching is…

Given a string `s`, return `true` if it is a pangram and `false` otherwise. A pangram contains every English letter from `a` through `z` at least once. Matching is case-insensitive, and non-letter characters are ignored.

- `0 ≤ s.length ≤ 10^5` - `s` contains printable ASCII characters. - The interactive visualizer accepts at most 40 characters; longer valid judge inputs remain execution-only.

Example 1: input s = "The quick brown fox jumps over the lazy dog"; output true. Every English letter occurs at least once.

Example 2: input s = "algorithm"; output false. Several letters, including b and c, are missing.

Example 3: input s = "Sphinx of black quartz, judge my vow!"; output true. Case and punctuation do not affect letter membership.

Category: Strings. Topic: strings. Difficulty: Easy. Patterns: hashing.