Let say I have 2 Columns (A = Section, B=Class).
Section Class Value
Section1 A 1
Section2 B 1
Section3 A 1
Section2 D 1
Section1 B 1
Section2 A 1
Section1 B 1
Section1 E 1
Section1 A 1
Section2 A 1

The result I want is :
Column A,B, C - is sorted, but if Section and Class is the same, only
one will be displayed and the value is added in column C.
The result will be :

Section Class Value
Section1 A 2
Section1 B 2
Section1 E 1
Section2 A 2
Section2 B 1
Section2 D 1
Section3 A 1

Would apreciate your help.
Thanks