Excel: find indices of value in list then return largest index value from other column

Excel: find indices of value in list then return largest index value from
other column

I have a small excel spreadsheet with 2 columns. One with values, the
other with dates. Eg.
A B
1 1/1/11
2 1/4/12
3 3/3/13
1 12/4/12
3 2/2/11
I want to
search a value in column A (that value may occur multiple times) and get
the row indices where it occurs.
get the largest (MAX) date from column B associated with the value that i
searched for in column A using the search indices.
E.g., I search for 1 and get back 12/4/12.
Ideally i would like to perform steps 1 and 2 in a single command. Help?
thank you!