add as

#include <iostream>
#include <vector>
using namespace std;
vector<char>reka;
int n,m;
const int INF = 10000000;
int solve(int x, int y){
    if(reka[x] == -1){
        return 0;
    }
    if(x == n){
        if( y == 0){
            return 1;
        }
        else{
            return 0;
        }
    }

    if (reka[x] == 'L' && y == 0){
        int kek1 = solve(x+1,0) ;
        int kek2 = solve(x+1,1) ;
        int rt = min(kek1, kek2);
        int p;
        if(rt == kek1){
            p = 0;
        }
        else{
            p = 1;
        }
        return solve(x+1, p) + 1;
    }
    if (reka[x] ==  'R'  && y == 1){
        int kek1 = solve(x+1,0);
        int kek2 = solve(x+1,1) ;
        int rt = min(kek1, kek2);
        int p;
        if(rt == kek1){
            p = 0;
        }
        else{
            p = 1;
        }
        return solve(x+1, p) + 1;
    }
    if (reka[x] == 'B'){
        return solve(x+1, y) + 1;
    }
    return solve(x+1,y);

}
int main(){
    string a;
    cin>>a;
    n = a.size();
    for(int i = 0; i < a.size(); ++i){
        reka.push_back(a[i]);
    }

    int yt = solve(0,0) ;
    cout<<yt<<endl;
    return 0;
}