Geometric Data

Computer graphics uses polygon models as a way to represent three-dimensional shapes. A polygon model is a model that creates a surface by giving the coordinates of vertices and how to connect those vertices.

A general polygon model can handle any polygon, but this time we will consider a polygon model consisting of triangles. Any polygon model can be represented as a collection of surface information that represents a triangle.

One surface information represents three vertices side by side. However, if the same 3 points are arranged only in different arrangements, the same surface information will be represented. For example, in the tetrahedron shown below, the faces formed by connecting vertices 1, 2, and 3 can be represented as vertices 2, 3, 1, and vertices 3, 2, 1. In this way, if there are multiple pieces of the same surface information, it will be useless, so it is better to combine them into one.

Given the surface information, write a program to find the number of surface information that must be erased to eliminate duplicate surfaces.

Input

The input is given in the following format.

N p11 p12 p13 p21 p22 p23 :: pN1 pN2 pN3

The number N (1 ≤ N ≤ 1000) of the surface information of the polygon model is given in the first line. The next N lines are given the number of vertices pij (1 ≤ pij ≤ 1000) used to create the i-th face. However, the same vertex is never used more than once for one face (pi1 ≠ pi2 and pi2 ≠ pi3 and pi1 ≠ pi3).

Output

Output the number of surface information that must be erased in order to eliminate duplicate surfaces on one line.

Examples

Input

4 1 3 2 1 2 4 1 4 3 2 3 4

Output

0

Input

6 1 3 2 1 2 4 1 4 3 2 3 4 3 2 1 2 3 1

Output

2

inputFormat

Input

The input is given in the following format.

N p11 p12 p13 p21 p22 p23 :: pN1 pN2 pN3

The number N (1 ≤ N ≤ 1000) of the surface information of the polygon model is given in the first line. The next N lines are given the number of vertices pij (1 ≤ pij ≤ 1000) used to create the i-th face. However, the same vertex is never used more than once for one face (pi1 ≠ pi2 and pi2 ≠ pi3 and pi1 ≠ pi3).

outputFormat

Output

Output the number of surface information that must be erased in order to eliminate duplicate surfaces on one line.

Examples

Input

4 1 3 2 1 2 4 1 4 3 2 3 4

Output

0

Input

6 1 3 2 1 2 4 1 4 3 2 3 4 3 2 1 2 3 1

Output

2

样例

4
1 3 2
1 2 4
1 4 3
2 3 4

0