How to replace only certain item value?

Grasshopper
#1

here is my problem…
I only want to replace 1 and 3 by 10 and 30…

thanks !!!

value
value.PNG1496×567 49.1 KB

#2

Check attached…

Canvas%20at%2019%3B07%3B05
Canvas at 19;07;05.png720×521 35.8 KB

1 Like
#3

so easy… so smart, it work perfectly thank you very much !