{

constexpr size_t POINT_NUM = 4;

constexpr size_t DIM = 2;

constexpr size_t K = 2;

ANNcoord coordinate[POINT_NUM * DIM]{

0, 0,

0, 1,

1, 0,

1, 1

};

ANNpointArray ptsArr = annAllocPts(POINT_NUM, DIM);

for (size_t i = 0; i < POINT_NUM; ++i)

{

for (size_t j = 0; j < DIM; ++j)

{

ptsArr[i][j] = coordinate[i * DIM + j];

}

}

ANNbd_tree tree(ptsArr, POINT_NUM, DIM);

ANNpoint queryPt = annAllocPt(2);

ANNidx idxArr[K];

ANNdist distArr[K];

queryPt[0] = 0.2;

queryPt[1] = 0.1;

tree.annkSearch(queryPt, K, idxArr, distArr);

std::cout << "idx:" << std::endl;

for (size_t i = 0; i < K; i++)

{

std::cout << "- ptsArr[" << idxArr[i] << "]:";

for (size_t j = 0; j < DIM; j++)

{

std::cout << " " << ptsArr[i][j];

}

std::cout << std::endl;

}

std::cout << "dist: ";

for (double i : distArr)

std::cout << " " << i;

std::cout << std::endl;

annDeallocPts(ptsArr);

}