title: Find The Number Occurring Odd Number Of Times
signature: int findTheNumberOccurringOddNumberOfTimes(vector<int> arr, int arr_size) {
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(int actual, int expected){
      return actual == expected;
  }
  
  string driver(vector<int> arr, int arr_size, int expected){
      try
      {
          if (validateSolution(PLACEHOLDER_FN_NAME(arr, arr_size), 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({1, 5, 5, 8, 14, 15, 17, 17, 18, 23, 23, 25, 26, 35, 36, 39, 51, 53, 56, 56, 60, 62, 64, 64, 65, 66, 67, 68, 71, 75, 80, 82, 83, 88, 89, 91, 91, 92, 93, 95, 99}, 31, 1); 
      cout << "TEST-" << 0 << "..."
           <<  result
           << "\n";
  
      result = driver({-56, 98, 44, 30, -88, 18, 60, 86, 4, 16, 10, 64, -22, -86, -66, -16, 70, -44, 98, 78, -96, -66, 92, 10, 40, -16}, 19, -56); 
      cout << "TEST-" << 1 << "..."
           <<  result
           << "\n";
  
      result = driver({0, 0, 0, 0, 0, 1, 1, 1}, 6, 0); 
      cout << "TEST-" << 2 << "..."
           <<  result
           << "\n";
  
      result = driver({36, 11, 83, 41, 42, 14, 46, 89, 91, 96, 57, 42, 74, 73, 9, 26, 79, 40, 31, 69, 44, 39, 14, 92, 34, 20, 52, 47, 14}, 25, 36); 
      cout << "TEST-" << 3 << "..."
           <<  result
           << "\n";
  
      result = driver({-84, -84, -84, -78, -66, -62, -62, -36, -24, -10, -10, -8, -4, -2, 12, 14, 20, 22, 36, 42, 46, 66, 84, 96, 96, 98}, 23, -84); 
      cout << "TEST-" << 4 << "..."
           <<  result
           << "\n";
  
      result = driver({1, 1, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1}, 19, 1); 
      cout << "TEST-" << 5 << "..."
           <<  result
           << "\n";
  
      result = driver({11, 12, 14, 28, 42, 48, 50, 58, 67, 74, 86, 89, 95}, 7, 11); 
      cout << "TEST-" << 6 << "..."
           <<  result
           << "\n";
  
      result = driver({52, -56, -6, 74, 10, 68, 74, 10, 16, -80, 82, -32, 6, -6, 82, 20}, 11, 52); 
      cout << "TEST-" << 7 << "..."
           <<  result
           << "\n";
  
      result = driver({0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, 31, 0); 
      cout << "TEST-" << 8 << "..."
           <<  result
           << "\n";
  
      result = driver({4, 80, 92}, 1, 4); 
      cout << "TEST-" << 9 << "..."
           <<  result
           << "\n";
  
      return 0;
  }
source_py: def find_the_number_occurring_odd_number_of_times(arr, arr_size):
      for i in range(0, arr_size):
          count = 0
          for j in range(0, arr_size):
              if (arr[i] == arr[j]):
                  count += 1
          if ((count % 2) != 0):
              return arr[i]
      return (- 1)
source_cpp: int find_the_number_occurring_odd_number_of_times(vector<int> arr, int arr_size) {
    for ( int i = 0;
    i < arr_size;
    i ++ ) {
      int count = 0;
      for ( int j = 0;
      j < arr_size;
      j ++ ) {
        if ( arr [ i ] == arr [ j ] ) count ++;
      }
      if ( count % 2 != 0 ) return arr [ i ];
    }
    return - 1;
  }