title: Tail Recursion
signature: func tailRecursion(n int) int64 {
test_code: package main
  
  import (
      "fmt"
      "reflect"
      "math"
      "sort"
  )
  
  // SOLUTION CODE
  // ===================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE
  // ===================================
  func validateSolution(actual int64, expected int64) bool {
      return reflect.DeepEqual(actual,expected)
  }
  
  func driver(n int, expected int64) string {
      if validateSolution(PLACEHOLDER_FN_NAME(n),expected) {
              return "PASSED"
      }
      return "FAILED"
  
  }
  
  func main() {
  
      // Use imports to avoid undefined errors
      var _ = reflect.DeepEqual
      _ = math.Abs
      _ = sort.Sort
      result := ""
      result = driver(16, 20922789888000)
      fmt.Printf("TEST-0...%s\n", result)
      
          
  }
source_py: def tail_recursion(n):
      if (n == 0):
          return 1
      return (n * tail_recursion((n - 1)))
source_cpp: unsigned int tail_recursion(unsigned int n) {
    if ( n == 0 ) return 1;
    return n * tail_recursion ( n - 1 );
  }