I didn't understood how we arrived at even and odd case

#1

Please explain even and odd case.

#2

Hi
approach for this question will be like

if i is even
dp[i]= min(dp[i/2]+x,dp[i-1]+y} ;

if i is odd
dp[i]=min(dp[i-1]+y,dp[i+1/2]+x+z} ;

for more explanation have a look at video, it’s in the course ( advance dp cell mitosis) , if you have doubt in approach please do post.