comparing 2 columns and count results

i have a serious problem. I have been trying to do a conditional countif.
I have 2 columns of data.

A B
1 0
1 2
1 2
1 2
2 4
2 1
2 3
2 3
2 1
2 3
3 0
I need to count how many times when A = 1, B=0
I need to count how many times when A = 1, B=1
I need to count how many times when A = 1, B=2
I need to count how many times when A = 1, B=3
I need to count how many times when A = 1, B=4
I need to count how many times when A = 2, B=0
I need to count how many times when A = 2, B=1
I need to count how many times when A = 2, B=2
I need to count how many times when A = 2, B=3
I need to count how many times when A = 2, B=4
and so on for 45001 rows
the range on A is 1-12
The range on B is 0-26

Can someone please help me?

Use a pivot table