a.#include <bits/stdc++.h>
using namespace std;
int main(){
int n,s=0;
cin>>n;
while(n){
if((n%10)%2==1)
s+=n%10;
n/=10;
}
cout<<s;
}
b.#include <bits/stdc++.h>
using namespace std;
int main(){
int n,a,cp,inv,maxpal=-1;
cin>>n;
for(int i=1;i<=n;++i){
cin>>a;
cp=a;
inv=0;
while(cp){
inv=inv*10+cp%10;
cp/=10;
}
if(inv==a && a>maxpal)
maxpal=a;
}
if(maxpal==-1)
cout<<"Nu exista numere palindrom";
else
cout<<maxpal;
}