Solution

196228

Problem / game
First name
Ruel
School
Clifton Hill Primary School
School's Twitter handle
We have none
Country
Age
12

Essentially this problem is impossible as the bot will always find a way to make 18 which I 1 away from 19 the lowest possible number that you can win by however if you start with 3 the a.i will go to 4-7 add 4-1 to get to 8 then if it adds 1-4 make it 13 then just make 18 after it makes 14-17
then you win.