#include #include #include using namespace std; typedef long long ll; #define rep(i,n) for(int i=0;i<(n);i++) int dp[110]; int grundy(int x){ if(dp[x] != -1)return dp[x]; if(x <= 1)return dp[x] = 0; set s; //状態遷移 if(x % 2 == 0 && x >= 2) s.insert(grundy(x / 2) ^ grundy(x / 2)); if(x % 2 == 1 && x >= 3) s.insert(grundy(x / 2) ^ grundy(x / 2 + 1)); if(x % 3 == 0 && x >= 3) s.insert(grundy(x / 3) ^ grundy(x / 3) ^ grundy(x / 3)); if(x % 3 == 1 && x >= 4) s.insert(grundy(x / 3) ^ grundy(x / 3) ^ grundy(x / 3 + 1)); if(x % 3 == 2 && x >= 5) s.insert(grundy(x / 3) ^ grundy(x / 3 + 1) ^ grundy(x / 3 + 1)); int res = 0; while(s.count(res)) res++; return dp[x] = res; } int main(void){ rep(i, 110) dp[i] = -1; int n; cin >> n; if(grundy(n) == 0){ printf("B\n"); }else{ printf("A\n"); } return 0; }