A question on Sololearn ( c++)

This must be a very very easy problem but I’m a beginner and I came across this when learning on sololearn.
Thnx for help!

https://forum.usaco.guide/t/how-to-ask-for-help-on-a-problem/338/2

this is the link to this problem https://www.sololearn.com/learning/eom-project/1051/904