title: Divisibility By 7
signature: bool divisibilityBy7(int num) {
test_code: #include <algorithm>
  #include <assert.h>
  #include <cstdlib>
  #include <iostream>
  #include <map>
  #include <set>
  #include <string>
  #include <tuple> 
  #include <unordered_map>
  #include <vector>
  #include <math.h>
  #include <cmath>
  #include <bits/stdc++.h>
  #include <numeric>
  #include <functional>
  
  using namespace std;
  
  // SOLUTION CODE
  // ============================================
  PLACEHOLDER_CODE_BODY
  
  // TESTING CODE 
  // ============================================
  bool validateSolution(bool actual, bool expected){
      return actual == expected;
  }
  
  string driver(int num, bool expected){
      try
      {
          if (validateSolution(PLACEHOLDER_FN_NAME(num), expected)){
              return "PASSED";
          }
          return "FAILED";
      }
      catch (const std::overflow_error& exception_obj)
      {
          return typeid(exception_obj).name();
      }
      catch (const std::runtime_error& exception_obj)
      {
          return typeid(exception_obj).name();
      }
      catch (const std::exception& exception_obj)
      {
          return typeid(exception_obj).name();
      }
      catch (...)
      {
          return "UNK_ERROR";
      }
  }
  
  int main() {
      string result = "";
  
      result = driver(0, true); 
      cout << "TEST-" << 0 << "..."
           <<  result
           << "\n";
  
      result = driver(-21, false); 
      cout << "TEST-" << 1 << "..."
           <<  result
           << "\n";
  
      result = driver(7, true); 
      cout << "TEST-" << 2 << "..."
           <<  result
           << "\n";
  
      result = driver(63, false); 
      cout << "TEST-" << 3 << "..."
           <<  result
           << "\n";
  
      result = driver(84, false); 
      cout << "TEST-" << 4 << "..."
           <<  result
           << "\n";
  
      result = driver(73, false); 
      cout << "TEST-" << 5 << "..."
           <<  result
           << "\n";
  
      result = driver(81, false); 
      cout << "TEST-" << 6 << "..."
           <<  result
           << "\n";
  
      result = driver(-10, false); 
      cout << "TEST-" << 7 << "..."
           <<  result
           << "\n";
  
      result = driver(47, false); 
      cout << "TEST-" << 8 << "..."
           <<  result
           << "\n";
  
      result = driver(23, false); 
      cout << "TEST-" << 9 << "..."
           <<  result
           << "\n";
  
      return 0;
  }
source_py: def divisibility_by_7(num):
      if (num < 0):
          return divisibility_by_7((- num))
      if ((num == 0) or (num == 7)):
          return True
      if (num < 10):
          return False
      return divisibility_by_7(((num / 10) - (2 * (num - ((num / 10) * 10)))))
source_cpp: int divisibility_by_7(int num) {
    if ( num < 0 ) return divisibility_by_7 ( - num );
    if ( num == 0 || num == 7 ) return 1;
    if ( num < 10 ) return 0;
    return divisibility_by_7 ( num / 10 - 2 * ( num - num / 10 * 10 ) );
  }