#include <stdio.h>

int main()
{
	int a,b,c,maxi,mini;
	char aa = 'A',bb = 'B',cc = 'C',max,tyu,min;

	scanf("%d",&a);
	scanf("%d",&b);
	scanf("%d",&c);

	if(a > b){
		max = aa;
		maxi = a;
		min = bb;
		mini = b;
	} else {
		max = bb;
		maxi = b;
		min = aa;
		mini = a;
	}

	if (c > maxi){
		tyu = max;
		max = cc;
	} else if(mini > c){
		tyu = min;
		min = cc;
	} else {
		tyu = cc;
	}

	printf("%c\n%c\n%c\n",max,tyu,min);
	return(0);
}