Details on missing data in R

#1
Hello all,

Say I have data as shown below. I want to generate a report in R like this:
Missing 0 tests: 1
Missing 1 test: 2
Missing 2 tests: 2
Missing 3 tests: 1

I then want to generate a report that says the combination of missing values. For example, 1/3 of respondents who were missing test3 were also missing test1




PHP:
id	test1	test2	test3
100	100	   20	   NA
101	71	   28	   NA
102	50	   82	   10
103	NA	   NA	   57
104	NA	   NA	   NA
105	76	   NA	   98