Can someone please help in parsing the following data. Below are the input, output and tried attempt details.

Input data:

foo 1
bar 12
foo 23
foo 45
bar 223
bar 123
bar 3478
foo 45
zoo 1
zoo 0987
foo 5

Output data:

foo 1 23 45 45 5

bar 12 223 123 3478 

zoo 1 0987

Attempt(Failed):

awk '{a[$1]=$2;next}END{for(i in a) print i,a[i]}' input
zoo 0987
foo 5
bar 3478