union array

hi
i have 3 array below like :

arr1(0)=1 arr1(1)=2 arr1(2)=3
arr2(0)=2 arr2(1)=3 arr2(2)=4
arr3(0)=3 arr3(1)=2 arr3(2)=5

i want to marge them ,namely my result be nelow like :
result 1,2,3,4,5

i need to a solution quick for this work
it's urgent
please help me
thanks