I'm wanting to lookup up one value in a list of other values and return the
sum of the values in the column next to it but can't figure out how.

For example, I have a list of items in column N. I want the sum from column
H each time the item in Column N appears in Column G. So basically anytime
the item in Column N appears in Column G, I want it to sum each value in
Column H in the corresponding (same row that the data appeared in in column G

Column G Column H
Allen 45
ABA 113
A&B 75
A&B 65
A&B 235
Accu 117
Accu 85
Ahaus 10

Say I have A&B in column N (I'm working in column O)....I want to know the
sum for A&B...so it should return 375.

Any help?