package main

import (
	"fmt"
	"sort"
)

func main() {
	var h int
	var hs = make(map[int]string, 3)
	fmt.Scan(&h)
	hs[h] = "A"
	fmt.Scan(&h)
	hs[h] = "B"
	fmt.Scan(&h)
	hs[h] = "C"
	a := make([]int, 0)
	for k := range hs {
		a = append(a, k)
	}
	sort.Sort(sort.Reverse(sort.IntSlice(a)))
	for _, v := range a {
		fmt.Println(hs[v])
	}
}