title: Dyck Path
signature: dyck_path <- function(n) {
test_code: 
  
  
  # SOLUTION CODE
  # ============================================
  PLACEHOLDER_CODE_BODY
  
  # TESTING CODE 
  # ============================================
  validate_solution <- function(actual, expected) {
      abs(actual - expected) < 1e-09
  }
  
  driver <- function(n, expected){
      if (validate_solution(PLACEHOLDER_FN_NAME(n), expected)){
          "PASSED"
      } else{
          "FAILED"
      }
  }
  
  main <- function() {
      cat(sprintf("TEST-0...%s\n",driver(
          28L, 
          263747951750360.03
      )))
  
      cat(sprintf("TEST-1...%s\n",driver(
          13L, 
          742900.0
      )))
  
      cat(sprintf("TEST-2...%s\n",driver(
          7L, 
          429.0
      )))
  
  }
  
  main()
source_py: def dyck_path(n):
      res = 1
      for i in range(0, n):
          res *= ((2 * n) - i)
          res /= (i + 1)
      return (res / (n + 1))
source_cpp: int dyck_path(unsigned int n) {
    int res = 1;
    for ( int i = 0;
    i < n;
    ++ i ) {
      res *= ( 2 * n - i );
      res /= ( i + 1 );
    }
    return res / ( n + 1 );
  }