include

include

include

include

include

using namespace std;

int main(){

char a[100001],b[100001]={};int k=0;
cin>>a;
for(int i=0;i<strlen(a);i++){
	if((int)a[i]%3!=0){
		b[k]=a[i];
		k++;
	}
}
char c;
for(int i=0;i<strlen(b);i++){
	for(int j=0;j<strlen(b)-i-1;j++){
		if(b[j]>b[j+1]){
			c=b[j+1];
			b[j+1]=b[j];
			b[j]=c;
		}
	}
}
for(int i=0;i<strlen(b);i++){
	cout<<b[i];
}
return 0;

}