 
 // Called from driver program.  Handles running GPU calculation
 extern "C" void gpu_dotProduct(long long *result_array, int num_vectors) {
-  int *distance_array_d;
-  int *force_array_d;
+  long long *distance_array_d;
+  long long *force_array_d;
   long long *result_array_d;
 
   // allocate space in the device
-  cudaMalloc((void **)&distance_array_d, sizeof(int) * num_vectors);
-  cudaMalloc((void **)&force_array_d, sizeof(int) * num_vectors);
+  cudaMalloc((void **)&distance_array_d, sizeof(long long) * num_vectors);
+  cudaMalloc((void **)&force_array_d, sizeof(long long) * num_vectors);
   cudaMalloc((void **)&result_array_d, sizeof(long long) * num_vectors);
 
   cudaMemcpy(result_array_d, result_array, sizeof(long long) * num_vectors,

 */
#define BLOCK_SIZE 32

__global__ void cu_dotProduct(int *distance_array_d, int *force_array_d,
                              long long *result_array_d, int max) {
  long long x;
  x = blockIdx.x * BLOCK_SIZE + threadIdx.x;

  }
}

__global__ void cu_gen_distance_array(long long *distance_array_d, int max) {
  int x;
  x = blockIdx.x * BLOCK_SIZE + threadIdx.x;
  distance_array_d[x] = (x + 1) % 10;
