#include<bits/stdc++.h>
using namespace std;
#define rep(i,n) for(ll i=0;i<n;i++)
#define repl(i,l,r) for(ll i=(l);i<(r);i++)
#define per(i,n) for(ll i=(n)-1;i>=0;i--)
#define perl(i,r,l) for(ll i=r-1;i>=l;i--)
#define fi first
#define se second
#define pb push_back
#define ins insert
#define pqueue(x) priority_queue<x,vector<x>,greater<x>>
#define all(x) (x).begin(),(x).end()
#define CST(x) cout<<fixed<<setprecision(x)
#define rev(x) reverse(x);
using ll=long long;
using vl=vector<ll>;
using vvl=vector<vector<ll>>;
using pl=pair<ll,ll>;
using vpl=vector<pl>;
using vvpl=vector<vpl>;
const ll MOD=1000000007;
const ll MOD9=998244353;
const int inf=2e9+1;
const ll INF=4e18;
const ll dy[8]={-1,0,1,0,1,1,-1,-1};
const ll dx[8]={0,-1,0,1,1,-1,1,-1};
template <typename T> inline bool chmax(T &a, T b) {
  return ((a < b) ? (a = b, true) : (false));
}
template <typename T> inline bool chmin(T &a, T b) {
  return ((a > b) ? (a = b, true) : (false));
}
string t="KUROI?";
int main(){
    string s;cin >> s;
    string ns;
    rep(i,s.size()){
        rep(j,6)if(s[i]==t[j])ns+=s[i];
    }
    s=ns;
    set<vl> st;vl v(5);st.insert(v);
    rep(i,s.size()){
        set<vl> nst;
        if(s[i]=='?'){
            for(auto p:st){
                p[0]++;
                nst.insert(p);
                p[0]--;
                rep(j,4){
                    p[j]--;p[j+1]++;
                    if(p[j]>=0){
                        nst.insert(p);
                    }
                    p[j]++;p[j+1]--;
                }
            }
        }
        rep(j,5){
            if(s[i]==t[j]){
                if(!j){
                    for(auto p:st){
                        p[0]++;
                        nst.insert(p);
                    }
                }
                else{
                   for(auto p:st){
                       p[j-1]--;p[j]++;
                       if(p[j-1]>=0)nst.insert(p);
                    } 
                }
            }
        }
        swap(st,nst);
    }
    ll ans=0;
    for(auto z:st){
        chmax(ans,z.back());
    }
    cout << ans << endl;
}