Solution -- Hackerrank

#include <iostream>
#include <numeric>

auto balanceIndex(const int array[], const int count) -> int {
   auto rightPartition = std::accumulate(array + 1, array + count, 0);
   auto leftPartition = 0;

   for(auto index = 0; (index + 1) < count; index++) {
      rightPartition -= array[index + 1];
      leftPartition  += array[index];

      if(leftPartition == rightPartition)
        return (index + 1);
   }

   return -1;
}

auto main() -> int {
    auto count(0);
    std::cin >> count;

    auto array = new int[count];

    for(auto index = 0; index < count; index++)
        std::cin >> array[index];

    std::cout << balanceIndex(array, count);
}