硬貨の問題

fn main() {
   let C: [i32; 6] = [3, 2, 1, 3, 0, 2];
   let mut A = 620;

   let V: [i32; 6] = [1, 5, 10, 50, 100, 500];

   let mut ans: i32 = 0;

   for i in (0..6).rev() {
      let t = std::cmp::min(A / V[i], C[i]);
      A -= t * V[i];
      ans += t;
   }

   println!("{}", ans);
}