#include <algorithm>
#include <cstdio>
#include <cstdlib>
#include <cctype>
#include <cmath>
#include <iostream>
#include <sstream>
#include <string>
#include <utility>
#include <vector>
using namespace std;
#define FOREACH(it,c) for(typeof((c).begin()) it=(c).begin();it!=(c).end();++it)
template<class T> inline int size(const T&c) { return c.size(); }
 
int RIGHT_LIMIT, WRONG_LIMIT;
string s;
 
int cache[2501][51][51];
 
int f(int poz, int rr, int ww) {
  int &res = cache[poz][rr][ww];
  if(res!=-1) return res;
  if(poz==size(s)) { res=0; return res; }
  res = 0;
  if(rr>0) {
    res = max(res, (s[poz]=='G') + f(poz+1, rr-1, WRONG_LIMIT));
  }
  if(ww>0) {
    res = max(res, (s[poz]=='B') + f(poz+1, RIGHT_LIMIT, ww-1));
  }
  return res;
}
 
struct Horoscope {
 
  // MAIN
  int maxGoodDays(vector <string> predictions, int R, int W) {
    RIGHT_LIMIT = R; WRONG_LIMIT = W;
    s = ""; FOREACH(it,predictions) s += *it;
    memset(cache,-1,sizeof(cache));
    return f(0,RIGHT_LIMIT,WRONG_LIMIT);
  }
 
};
 
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