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My solution as Time Limit Exceeded:

I think it takes too much time to make array, but I cannot think of any way to make it more efficient...
How can I this code more efficient?

My solution - classified as Time Limit Exceeded:

I think it takes too much time to make the array, but I cannot think of any way to make it more efficient...
How can I this code more efficiently?

Problem

Time limit : 2sec / Memory limit : 256MB

Problem Statement
The season for Snuke Festival has come again this year. First of all, Ringo will perform a ritual to summon Snuke. For the ritual, he needs an altar, which consists of three parts, one in each of the three categories: upper, middle and lower.
He has N parts for each of the three categories. The size of the i-th upper part is Ai, the size of the i-th middle part is Bi, and the size of the i-th lower part is Ci.
To build an altar, the size of the middle part must be strictly greater than that of the upper part, and the size of the lower part must be strictly greater than that of the middle part. On the other hand, any three parts that satisfy these conditions can be combined to form an altar.
How many different altars can Ringo build? Here, two altars are considered different when at least one of the three parts used is different.

 

Constraints
1≤N≤10^5
1≤Ai≤10^9(1≤i≤N)
1≤Bi≤10^9(1≤i≤N)
1≤Ci≤10^9(1≤i≤N)
All input values are integers.

 

Input
Input is given from Standard Input in the following format:
N
A1 … AN
B1 … BN
C1 … CN

 

Output
Print the number of different altars that Ringo can build.

Problem Statement

The season for Snuke Festival has come again this year. First of all, Ringo will perform a ritual to summon Snuke. For the ritual, he needs an altar, which consists of three parts, one in each of the three categories: upper, middle and lower.

He has \$N\$ parts for each of the three categories. The size of the \$i\$-th upper part is \$A_i\$, the size of the \$i\$-th middle part is \$B_i\$, and the size of the \$i\$-th lower part is \$C_i\$.

To build an altar, the size of the middle part must be strictly greater than that of the upper part, and the size of the lower part must be strictly greater than that of the middle part. On the other hand, any three parts that satisfy these conditions can be combined to form an altar.

How many different altars can Ringo build? Here, two altars are considered different when at least one of the three parts used is different.

Constraints

• \$1 ≤ N ≤ 10^5\$
• \$1 ≤ A_i ≤ 10^9 (1 ≤ i ≤ N)\$
• \$1 ≤ B_i ≤ 10^9 (1 ≤ i ≤ N)\$
• \$1 ≤ C_i ≤ 10^9 (1 ≤ i ≤ N)\$

All input values are integers.

Time limit: 2 sec / Memory limit: 256 MB

Input

Input is given from Standard Input in the following format:

N
A1 … AN
B1 … BN
C1 … CN

Output

Print the number of different altars that Ringo can build.