pub fn judge_circle(moves: &str) -> bool {
if moves.len() == 0 {
return true;
}
let mut move_counts: std::collections::HashMap<char,i32> = std::collections::HashMap::new();
move_counts.insert('U',0);
move_counts.insert('D',0);
move_counts.insert('R',0);
move_counts.insert('L',0);
for character in moves.chars() {
*move_counts.entry(character).or_insert(0) += 1;
}
let Some(first) = move_counts.get(&'U') else { todo!() };
let Some(second) = move_counts.get(&'D') else { todo!() };
let Some(third) = move_counts.get(&'R') else { todo!() };
let Some(fourth) = move_counts.get(&'L') else { todo!() };
return fourth == third && first == second;
}