// need
#include <iostream>
#include <algorithm>

// data structure
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
//#include <array>
#include <unordered_map>
//#include <complex>
//#include <deque>
#include <valarray>

// stream
//#include <istream>
#include <sstream>
//#include <ostream>
//#include <fstream>

// etc
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <chrono>
#include <random>
#include <numeric>

//namespace std {
//	template < typename T > std::string to_string(const T& n) {
//		std::ostringstream stm;
//		stm << n;
//		return stm.str();
//	}
//	int stoi(std::string s, int tmp = 10) {
//		std::istringstream stm(s);
//		int res;
//		stm >> res;
//		return res;
//	}
//}

// input
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);
#define VAR(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__);
template<typename T> void MACRO_VAR_Scan(T& t) { std::cin >> t; }
template<typename First, typename...Rest>void MACRO_VAR_Scan(First& first, Rest&...rest) { std::cin >> first; MACRO_VAR_Scan(rest...); }
#define VEC_ROW(type, n, ...)std::vector<type> __VA_ARGS__;MACRO_VEC_ROW_Init(n, __VA_ARGS__); for(int i=0; i<n; ++i){MACRO_VEC_ROW_Scan(i, __VA_ARGS__);}
template<typename T> void MACRO_VEC_ROW_Init(int n, T& t) { t.resize(n); }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Init(int n, First& first, Rest&...rest) { first.resize(n); MACRO_VEC_ROW_Init(n, rest...); }
template<typename T> void MACRO_VEC_ROW_Scan(int p, T& t) { std::cin >> t[p]; }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Scan(int p, First& first, Rest&...rest) { std::cin >> first[p]; MACRO_VEC_ROW_Scan(p, rest...); }
#define VEC(type, c, n) std::vector<type> c(n);for(auto& i:c)std::cin>>i;
#define MAT(type, c, m, n) std::vector<std::vector<type>> c(m, std::vector<type>(n));for(auto& r:c)for(auto& i:r)std::cin>>i;

// output
#define OUT(d) std::cout<<d;
#define FOUT(n, d) std::cout<<std::fixed<<std::setprecision(n)<<d;
#define SOUT(n, c, d) std::cout<<std::setw(n)<<std::setfill(c)<<d;
#define SP std::cout<<" ";
#define TAB std::cout<<"\t";
#define BR std::cout<<"\n";
#define SPBR(i, n) std::cout<<(i + 1 == n ? '\n' : ' ');
#define ENDL std::cout<<std::endl;
#define FLUSH std::cout<<std::flush;
#define SHOW(d) {std::cerr << #d << "\t:" << d << "\n";}
#define SHOWVECTOR(v) {std::cerr << #v << "\t:";for(const auto& xxx : v){std::cerr << xxx << " ";}std::cerr << "\n";}
#define SHOWVECTOR2(v) {std::cerr << #v << "\t:\n";for(const auto& xxx : v){for(const auto& yyy : xxx){std::cerr << yyy << " ";}std::cerr << "\n";}}
#define SHOWQUEUE(a) {auto tmp(a);std::cerr << #a << "\t:";while(!tmp.empty()){std::cerr << tmp.front() << " ";tmp.pop();}std::cerr << "\n";}

// utility
#define ALL(a) (a).begin(),(a).end()
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define RFOR(i, a, b) for(int i=(b)-1;i>=(a);--i)
#define REP(i, n) for(int i=0;i<int(n);++i)
#define RREP(i, n) for(int i=int(n)-1;i>=0;--i)
#define FORLL(i, a, b) for(ll i=ll(a);i<ll(b);++i)
#define RFORLL(i, a, b) for(ll i=ll(b)-1;i>=ll(a);--i)
#define REPLL(i, n) for(ll i=0;i<ll(n);++i)
#define RREPLL(i, n) for(ll i=ll(n)-1;i>=0;--i)
#define IN(a, x, b) (a<=x && x<b)
template<typename T> inline T CHMAX(T& a, const T b) { return a = (a < b) ? b : a; }
template<typename T> inline T CHMIN(T& a, const T b) { return a = (a > b) ? b : a; }
#define EXCEPTION(msg) throw std::string("Exception : " msg " [ in ") + __func__ + " : " + std::to_string(__LINE__) + " lines ]"
#define TRY(cond, msg) try {if (cond) EXCEPTION(msg);}catch (std::string s) {std::cerr << s << std::endl;}
void CHECKTIME(std::function<void()> f) { auto start = std::chrono::system_clock::now(); f(); auto end = std::chrono::system_clock::now(); auto res = std::chrono::duration_cast<std::chrono::nanoseconds>((end - start)).count(); std::cerr << "[Time:" << res << "ns  (" << res / (1.0e9) << "s)]\n"; }

// test
template<class T> std::vector<std::vector<T>> VV(int n) {
	return std::vector<std::vector<T>>(n);
}
template<class T> std::vector<std::vector<T>> VV(int n, int m, T init = T()) {
	return std::vector<std::vector<T>>(n, std::vector<T>(m, init));
}
template<typename S, typename T>
std::ostream& operator<<(std::ostream& os, std::pair<S, T> p) {
	os << "(" << p.first << ", " << p.second << ")"; return os;
}

// type/const

#define int ll
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using PAIR = std::pair<int, int>;
using PAIRLL = std::pair<ll, ll>;
constexpr int INFINT = 1 << 30;                          // 1.07x10^ 9
constexpr int INFINT_LIM = (1LL << 31) - 1;              // 2.15x10^ 9
constexpr ll INFLL = 1LL << 60;                          // 1.15x10^18
constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62);  // 9.22x10^18
constexpr double EPS = 1e-9;
constexpr int MOD = 1000000007;
constexpr double PI = 3.141592653589793238462643383279;


std::string process(std::string s) {
	int n = s.size();
	int p = 0;
	int dir = 1;
	while (IN(0, p, n)) {
		if (s[p] == 'A') {
			s[p] = 'B';
			dir *= -1;
		}
		else {
			s[p] = 'A';
		}
		p += dir;
	}
	return s;
}

std::string decode(std::deque<int> deq, char c) {
	std::string res;
	while (!deq.empty()) {
		int now = deq.front(); deq.pop_front();
		res += std::string(now, c);
		c = 'A' + (c == 'A');
	}
	return res;
}

signed main() {
	INIT;

	if(0){
		VAR(std::string, s);
		int n = s.size();

		REP(i, n * 2 + 2) {
			SOUT(2, ' ', i)TAB OUT((s = process(s)))BR;
		}

		return 0;
	}

	VAR(int, n, k);
	VAR(std::string, s);

	std::deque<int> deq;
	char c = s[0];

	{
		int l = 0;
		FOR(r, 1, n + 1) {
			if (r == n || s[l] != s[r]) {
				deq.emplace_back(r - l);
				l = r;
			}
		}
	}

	if (k > 2 * n + 10) {
		k = 2 * n + k % 2;
	}

	REP(_, k) {
		int t = deq.front(); deq.pop_front();
		if (c == 'A') {
			c = 'B';
			if (t == 1) {
				if (deq.empty()) {
					deq.emplace_front(1);
				}
				else {
					int t2 = deq.front(); deq.pop_front();
					deq.emplace_front(1 + t2);
				}
			}
			else {
				deq.emplace_front(t - 1);
				deq.emplace_front(1);
			}
		}
		else {
			if (t != 1) {
				c = 'A';
				deq.emplace_front(t - 1);
			}
			if (!deq.empty() && deq.size() % 2 == 'B' - c) {
				int t2 = deq.back(); deq.pop_back();
				deq.emplace_back(t2 + 1);
			}
			else {
				deq.emplace_back(1);
			}
		}
		//SHOW(decode(deq, c));
	}

	std::string ans(decode(deq, c));
	OUT(ans)BR;

	return 0;
}

Measured memory_bytes: 3736