/**

public double cosineSimilarity(int[] A, int[] B) {

if (A == null || B == null || A.length == 0 || B.length == 0 || A.length != B.length) {

return 2;

}

double sumProduct = 0;

double sumASq = 0;

double sumBSq = 0;

for (int i = 0; i < A.length; i++) {

sumProduct += A[i]*B[i];

sumASq += A[i] * A[i];

sumBSq += B[i] * B[i];

}

if (sumASq == 0 && sumBSq == 0) {

return 2.0;

}

return sumProduct / (Math.sqrt(sumASq) * Math.sqrt(sumBSq));

}