You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: _799_champagne_tower.rs
    path of file: ./repos/rustgym/leetcode/src/d7
    
    the code of the file until where you have to start completion: struct Solution;

impl Solution {
    fn champagne_tower(poured: i32, query_row: i32, query_glass: i32) -> f64 {
        let query_row = query_row as usize;
        let query_glass = query_glass as usize;
        let mut a: Vec<Vec<f64>> = vec![vec![0.0; 101]; 101];
        a[0][0] = poured as f64;
        for i in 0..
    
fn test() {
    use assert_approx_eq::assert_approx_eq;
    let poured = 1;
    let query_glass = 1;
    let query_row = 1;
    let res = 0.0;
    assert_approx_eq!(
        Solution::champagne_tower(poured, query_row, query_glass),
        res
    );
    let poured = 2;
    let query_glass = 1;
    let query_row = 1;
    let res = 0.5;
    assert_approx_eq!(
        Solution::champagne_tower(poured, query_row, query_glass),
        res
    );
    let poured = 0;
    let query_glass = 2;
    let query_row = 0;
    let res = 0.0;
    assert_approx_eq!(
        Solution::champagne_tower(poured, query_row, query_glass),
        res
    );
    let poured = 1;
    let query_glass = 0;
    let query_row = 0;
    let res = 1.0;
    assert_approx_eq!(
        Solution::champagne_tower(poured, query_row, query_glass),
        res
    );
    let poured = 1_000_000_000;
    let query_glass = 99;
    let query_row = 99;
    let res = 0.0;
    assert_approx_eq!(
        Solution::champagne_tower(poured, query_row, query_glass),
        res
    );
}