#include <stdio.h>

int main(void)
{
	char n[10], u;
	scanf("%s", n);
	int i = 0, t = 0, s;
	while (n[i] > 0) {
		if (n[i] >= t) {
			t = n[i];
			s = i;
		}
		i++;
	}
	u = n[s];
	n[s] = n[0];
	n[0] = u;
	printf("%s\n", n);
}