#include <bits/stdc++.h>
#define For(i,a,b) for(int i=a;i<=b;i++)
#define Rev(i,a,b) for(int i=a;i>=b;i--)
#define Fin(file) freopen(file,"r",stdin)
#define Fout(file) freopen(file,"w",stdout)
using namespace std; using ll = long long;
#define printf(...) (0==0)
const int N=7505;
class Solver{
	int p,d,cur,tr[N*3]; vector<int> his;
public:
	void clear(int _p) { printf("================== clear(%d)\n",_p); p=_p; d=cur=0; for(int x:his) tr[x]=0;; his.clear(); }
	void sett(){
		printf("sett(%d)\n",p);
		his.push_back(p); tr[p]++; d--;
	}
	void move(int x){
		printf("move(%d)\n",x);
		if(x==1) d+=tr[p]*2,cur+=d,p++;
		else cur-=d,p--,d-=tr[p]*2;
	}
	int getv() { printf("getv=%d\n",cur); return cur; }
}S;
char ss[N]; int n,a[N],pp[N],pcnt,tmp[N],ans[N][N];
int main(){
	cin>>(ss+1); n=strlen(ss+1); For(i,1,n) { a[i]=(ss[i]=='H'); if(a[i]) pp[++pcnt]=i; }
	For(i,1,n) For(j,i,n) ans[i][j]=-1;
	pp[0]=0; pp[pcnt+1]=n+1;
	// Even 1
	For(i,1,pcnt-1){
		int p=pp[i]+pp[i+1]; S.clear(p);
		For(j,0,i-1){
			int l=i-j,r=i+1+j; if(r>pcnt) break;
			assert(p>=pp[l]+pp[r]); while(p>pp[l]+pp[r]) S.move(-1),p--;
			S.sett(); while(p>pp[l-1]+1+pp[r]) S.move(-1),p--;
			while(p<=pp[l]+pp[r+1]-1) tmp[p]=S.getv(),S.move(1),p++;
			For(x,pp[l-1]+1,pp[l]) For(y,pp[r],pp[r+1]-1) assert(ans[x][y]==-1),ans[x][y]=tmp[x+y],printf("ans[%d][%d]=%d\n",x,y,ans[x][y]);;
		}
	}
	// Odd 1
	For(i,1,pcnt){
		int p=pp[i]*2; S.clear(p);
		For(j,0,i-1){
			int l=i-j,r=i+j; if(r>pcnt) break;
			assert(p>=pp[l]+pp[r]); while(p>pp[l]+pp[r]) S.move(-1),p--;
			if(j) S.sett();; while(p>pp[l-1]+1+pp[r]) S.move(-1),p--;
			while(p<=pp[l]+pp[r+1]-1) tmp[p]=S.getv(),S.move(1),p++;
			For(x,pp[l-1]+1,pp[l]) For(y,pp[r],pp[r+1]-1) if(~(x+y)&1) assert(ans[x][y]==-1),ans[x][y]=tmp[x+y]+abs((x+y)/2-pp[i]),printf("ans[%d][%d]=%d\n",x,y,ans[x][y]);;
		}
	}
	For(i,0,pcnt) For(x,pp[i]+1,pp[i+1]-1) For(y,x,pp[i+1]-1) ans[x][y]=0;
	printf("\n");
	For(i,1,n) For(j,i,n) printf("ans[%d][%d]=%d\n",i,j,ans[i][j]);
	ll Ans=0; For(x,1,n) For(y,x,n) Ans+=ans[x][y];
	cout<<Ans<<'\n';
	return 0;
}