Cacher is the code snippet organizer for pro developers

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wwwbbrwrbrbrrbrbrwrwwrbwrwrrb
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rrr
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rwrwrwrwrwrwrwrwrwrwrwrwbwrwbwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwrwr
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wwwwwwwwwwwwwwwww
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bbrrrbrrrrrrrrbrbbbrbrrbrrrrbbbrbrbbbbbrbrrrbbrbbb
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rrwwwwbb
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rrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbbrrrrrrrrrrrrrrrrrrrrbbbbbbbbbbbbbbbbbbbb
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rrbbrbbbwbwwbwbbbbwwrrbbwbrwbrwbbbrbrwrwbrwwwrrbbrrwrbbrwbwrwwwrbrwwwwwrwbwwwrrbrrbbbrbrbbbrbbbrbbwbbbbbrbrrbrwwbrrrrwbwrwrbbwbwrbrbrwwbrrbwbrwwbwwwbrbwrwbwbrbbbwrbwwrrrbwbwbbbbbrrwwwrbrwwrbbwrbbrbbrbwrrwwbrrrbrwbrwwrbwbwrrrbwrwrrbrbbwrwrbrwwwrwbwrrwwwwrrrwrrwbbwrwwrwrbwwbwrrrrbbwrbbrbwwwwwbrbbrbbrbrwbbwbwwbbbbbwwwrbwwbbbwrwwbbrrwrwbwrrwwwrrrwrrwww
------- test 9 [length 338 bytes] ----
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rwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwbrwb

/*
PROG: beads
LANG: C++
*/
#include <iostream>
#include <fstream>
#include <string>
using namespace std;
 
int main() {
	ofstream fout ("beads.out");
    	ifstream fin ("beads.in");
 	int N;
 	fin >> N;
	string beads;
 	fin >> beads;
 
 	int cur = 0, max = 0;
 	char color;
 	bool switched;
  
 	for(int i = 0; i < N; ++i){
  		cur = 0;
  		switched = false;
  		color = 'w';
  		for(int j = 0; j < N; ++j){
   			const char cur_c = beads[(i + j) % N];
			 if(cur_c != 'w'){
    			if(color == 'w'){
     				color = cur_c;
    			}
    			else if(color != cur_c){
    				 if(switched)
      					break;
     				else{
      					color = cur_c;
      					switched = true;
     				}
    			}
   			}
   			++cur;
  		}
  		if(cur > max)
   			max = cur;
 	}
  
 	fout << max << endl;
 	return 0;
}