impl Solution {
    pub fn is_match(s: String, p: String) -> bool {
        ...
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_basic() {
        let s = "abc".to_string();
        let p = "a?c".to_string();
        // Replace false with the correct expected output when implemented.
        assert_eq!(Solution::is_match(s, p), true);
    }

    #[test]
    fn test_edge_case() {
        let s = "".to_string();
        let p = "".to_string();
        assert_eq!(Solution::is_match(s, p), true);
    }
}