Codeforces Round #334 (Div. 2) C. Lieges of Legendre

#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
const int maxm=1e5+10;
char s[maxm];
int main()
{
int n;
while(scanf("%d",&n)!=EOF)
{
scanf("%s",s);
int len=1;
for(int i=1;i<strlen(s);i++)
{
if(s[i]!=s[i-1])
len++;
}
printf("%d\n",min(len+2,n));
}
return 0;
}