let rec aux_simple = 
  (i: int): int => 
    if(i
    < 100) {
      aux_simple(i + 1)
    } else {
      i
    };

let counter_simple = (n: int): int => aux_simple(n);

type sum_aggregator = {counter: int, sum: int };

let counter = 
  (n: int): int => 
    {
      let initial: sum_aggregator = {counter = 0, sum = 0 };
      let rec aggregate = 
        (prev: sum_aggregator): int => 
          if(prev[counter]
          <= n) {
          
            
            aggregate({
                counter = prev[counter] + 1,
                sum = prev[counter] + prev[sum]
              })
          } else {
            prev[sum]
          };
      aggregate(initial)
    };

let rec aux_nest = 
  (prev: sum_aggregator): sum_aggregator => 
    if(prev[counter]
    < 100) {
    
      let sum: int = prev[sum] + aux_simple(prev[counter]);
      aux_nest({counter = prev[counter] + 1, sum = sum })
    } else {
      ({counter = prev[counter], sum = prev[sum] })
    };

let counter_nest = 
  (n: int): int => 
    {
      let initial: sum_aggregator = {counter = 0, sum = 0 };
      let out: sum_aggregator = aux_nest(initial);
      out[sum]
    };