Codeforces Round #325 (Div. 2) E. Alice, Bob, Oranges and Apples

模拟一下发现和gcd一样。。。于是按gcd模拟就好了。。。

#include<bits/stdc++.h>
using namespace std;
typedef long long LL;

void work()
{
	LL a, b;
	scanf("%I64d%I64d", &a, &b);
	if(__gcd(a, b) != 1) {
		printf("Impossible\n");
		return;
	}
	while(a && b) {
		if(a < b) {
			LL t = b / a;
			if(a * t == b) printf("%I64dB", t-1);
			else printf("%I64dB", t);
			b -= t * a;
		}
		else {
			LL t = a / b;
			if(b * t == a) printf("%I64dA", t-1);
			else printf("%I64dA", t);
			a -= t * b;
		}
	}
	printf("\n");
}

int main()
{
//freopen("data", "r", stdin);
	work();

	return 0;
}