Hi all

I am trying to solve this problem but unable to find the solution.

Any kind of hint would be great.

https://cses.fi/problemset/task/1754/

# Coin Piles problem from cses

This is what I did:

Try removing coins from bottom, It’s more intuitive that way.

```
if(a<b)swap(a,b);
if(a>2*b){
cout<<"NO\n";
}else{
a%=3,b%=3;
if(a<b)swap(a,b);
if((a==2 && b==1) || (a==b && b==0)){
cout<<"YES\n";
}else{
cout<<"NO\n";
}
}
```

1 Like

I really wish they had solutions for cses, It has really good problems.

got your idea thanks.

I was also thinking this way but couldn’t come with `a%=3,b%=3;`

this step.

1 Like

Here is my solution.

```
if(a<b) swap(a,b);
if(a>2*b)
{
cout<<"NO" << endl;
return 0;
}
if((a+b)%3==0)
{
cout<<"YES"<< endl;
}
else cout<<"NO"<< endl;
```