#include <stdio.h>

int main(){
	unsigned b1, b2, b3, max1=0, max2=0;

	scanf("%u %u %u", &b1, &b2, &b3);

	if(b1<100 || b1>999 || b2<100 || b2>999 || b3<100 || b3>999){
		printf("-1\n");
		return 1;
	}

	if(b1>b2){
		max1 = b1;
		max2 = b2;
	}else{
		max1 = b2;
		max2 = b1;
	}

	if(b3>max1){
		max2=max1;
		max1=b3;
	}else if(b3>max2)
		max2=b3;

	printf("%u\n", max1*1000+max2);

	return 0;
}