title: Number Ways Node Make Loop Size K Undirected Complete Connected Graph N Nodes
signature: numberWaysNodeMakeLoopSizeKUndirectedCompleteConnectedGraphNNodes(n, k) {
test_code: import 'dart:convert';
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  bool validateSolution(double actual, double expected){
      return (actual - expected).abs() < 1e-06;
  }
  
  String driver(n, k, double expected){
      try
      {
          if (validateSolution(PLACEHOLDER_FN_NAME(n, k), expected)){
              return "PASSED";
          }
          return "FAILED";
      }catch(exception_object){
          return exception_object.runtimeType.toString();
      }
  }
  
  int main() {
  
      print("TEST-0...${driver(
          16, 2, 
          15.0)
      }");
  
      return 0;
  }
source_py: def number_ways_node_make_loop_size_k_undirected_complete_connected_graph_n_nodes(n, k):
      p = 1
      if (k % 2):
          p = (- 1)
      return ((pow((n - 1), k) + (p * (n - 1))) / n)
source_cpp: int number_ways_node_make_loop_size_k_undirected_complete_connected_graph_n_nodes(int n, int k) {
    int p = 1;
    if ( k % 2 ) p = - 1;
    return ( pow ( n - 1, k ) + p * ( n - 1 ) ) / n;
  }