import java.util.*;
class Main {
public static void main(String[] args) {
//JSRUN引擎2.0,支持多达30种语言在线运行,全仿真在线交互输入输出。
Scanner scan = new Scanner(System.in);
int [] a = new int[10];
for(int j = 0;j<10;j++)
{
a[j] = scan.nextInt();
}
quickSort(a,0,9);
System.out.println(a[0]+""+a[1]+"");
}
public static void quickSort(int[] q, int l, int r) {
if (l >= r) return;
int i = l - 1, j = r + 1, x = q[l + r >> 1];
while (i < j) {
do i++; while (q[i] < x);
do j--; while (q[j] > x);
if (i < j) {
int temp = q[i];
q[i] = q[j];
q[j] = temp;
}
}
quickSort(q, l, j);
quickSort(q, j + 1, r);
}
}