// yukicoder: No.571 3人兄弟（その２）
// 2019.4.19 bal4u

#include <stdio.h>

#if 1
#define gc() getchar_unlocked()
#define pc(c) putchar_unlocked(c)
#else
#define gc() getchar()
#define pc(c) putchar(c)
#endif
int in()    // 非負整数の入力
{
	int n = 0, c = gc();
	do n = 10 * n + (c & 0xf), c = gc(); while (c >= '0');
	return n;
}

int main()
{
	int i, x[3], max, id;

	max = id = 0; for (i = 0; i < 3; i++) {
		x[i] = (in() << 7) - in();
		if (x[i] > max) max = x[i], id = i;
	}
	pc('A'+id), pc('\n'), x[id] = 0;

	max = 0; for (i = 0; i < 3; i++) {
		if (x[i] > max) max = x[i], id = i;
	}
	pc('A'+id), pc('\n'), x[id] = 0;

	for (i = 0; i < 3 && !x[i]; i++);
	pc('A' + i), pc('\n');
	return 0;
}