Katsusando loves omelette rice.
Besides, he loves crème brûlée, tenderloin steak and so on, and believes that these foods are all loved by everyone.
To prove that hypothesis, he conducted a survey on M kinds of foods and asked N people whether they like these foods or not.
The i-th person answered that he/she only likes the A_{i1}-th, A_{i2}-th, ..., A_{iK_i}-th food.
Find the number of the foods liked by all the N people.

-----Constraints-----
- All values in input are integers.
- $1 \leq N, M \leq 30$
- $1 \leq K_i \leq M$
- $1 \leq A_{ij} \leq M$
- For each $i (1 \leq i \leq N), A_{i1}, A_{i2}, ..., A_{iK_i}$ are distinct.

-----Constraints-----
Input is given from Standard Input in the following format:
N M
K_1 A_{11} A_{12} ... A_{1K_1}
K_2 A_{21} A_{22} ... A_{2K_2}
:
K_N A_{N1} A_{N2} ... A_{NK_N}

-----Output-----
Print the number of the foods liked by all the N people.

-----Sample Input-----
3 4
2 1 3
3 1 2 3
2 3 2

-----Sample Output-----
1

As only the third food is liked by all the three people, 1 should be printed.

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