Binary Search

while(low <= high){

                mid = (low +high) /2;
                if(Docs[mid].DocID > srchinfo->idx.block[i]){
                     high = mid -1;
                }else if(Docs[mid].DocID < srchinfo->idx.block[i])
                {
                    low = mid +1;
                }
                else
                {
                    CompareIDX[k].DocID = Docs[mid].DocID;
                    CompareIDX[k].Similarity  = Docs[mid].Similarity;
                    k++;
                    break;
                }
}