LeetCode 660. Remove 9

Problem Statement

impl Solution {
    pub fn new_integer(mut n: i32) -> i32 {
        let (mut ans, mut base) = (0, 1);
        while n > 0 {
            ans += n % 9 * base;
            n /= 9;
            base *= 10;
        }
        return ans;
    }
}