#include <bits/stdc++.h>
#define fr(a,b,c) for(int a=b,__=c;a<__;a++)
using namespace std;
typedef long long ll;
ll n,m;
string dp[51][51][51];

string go(int x,int y,int z){
	if(x==1&&y==0&&z==0)return "a";
	if(x==0&&y==1&&z==0)return "b";
	if(x==0&&y==0&&z==1)return "c";
	if(dp[x][y][z]!="")return dp[x][y][z];
	fr(i,0,x+1)fr(j,0,y+1)fr(k,0,z+1){
		if(i+j+k&&(i!=x||j!=y||k!=z)){
			string a=go(i,j,k);
			string b=go(x-i,y-j,z-k);
			if(a<b)a=a+b;
			else a=b+a;
			if(dp[x][y][z]<a)dp[x][y][z]=a;
		}
	}
	return dp[x][y][z]; 
}

int main(){
	int x,y,z;
	cin>>x>>y>>z;
	cout<<go(x,y,z)<<endl;
}