#include<bits/stdc++.h>
using namespace std;
const int MAXN=5008;
int n,k,a[MAXN],f[MAXN<<1],tag,op,ans=MAXN;
int ansk,sum;
inline int read()
{
    register int x=0,f=1;
    char s;
    while((s=getchar())<'0'||s>'9')
    {
        s=='-'?f=-1:f=1;
    }
    x=s-'0';
    while((s=getchar())>='0'&&s<='9')
    {
        x=x*10+s-'0';
    }
    return x*f;
}
int main()
{
	n=read();
	for(int i=1;i<=n;i++)
	{
		char s;
		cin>>s;
		if(s=='B') a[i]=0;
		if(s=='F') a[i]=1;
	}
	for(register int k=1;k<=n;k++)
	{
		sum=0;tag=0;op=0;
		memset(f,0,sizeof(f));
		for(register int i=1;i<=n;i++)
		{
			
			if((a[i]+tag)%2==0)
			{
				if(i+k-1>n)	
				{
					op=1;
					break;
				}
				++sum;
				++tag;
				f[i+k-1]=-1;
			}
			if(f[i]==-1)
			{
				--tag;
				f[i]=0;
			}
		}
		if(op) continue;
		if(sum<ans)
		{
			ans=sum;
			ansk=k;
		}
	}
	printf("%d %d",ansk,ans);
	return 0;
}

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这个原老师就是L啦！