algorithm - Number of Ranges that lie completely in a particular Range -

let have n ranges each specified by

 [l_i,r_i] 1<=i<=n 

and have query of type [l,r] in have find number of ranges among n ranges lie completely in given range i.e. [l,r]

example:

n ranges are:

here n 2.

2 4 3 3 

for query 3 5, output should 1.

for query 2 5 output should 2.

i know method o(m*n), n number of ranges , m number of queries, feels there must more efficient implementation.

yes, there is. data structure want called interval tree.