#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pll = pair<ll, ll>;
#define drep(i, cc, n) for (ll i = (cc); i <= (n); ++i)
#define rep(i, n) drep(i, 0, n - 1)
#define all(a) (a).begin(), (a).end()
#define pb push_back
#define fi first
#define se second

const ll MOD = 1000000007;
const ll MOD2 = 998244353;
const ll INF = 1LL << 60;
const ll MAX_N = 2e5;

struct SegmentTree{
    ll n;
    vector<pair<ll, bool>> dat;

    SegmentTree(ll n_){
        n = 1;
        while(n < n_) n*=2;
        dat.resize(2*n, {0, false});
    }

    void update(ll k, ll a){
        k += n-1;
        if(a == 1) dat[k] = {1, true};
        else dat[k] = {0, false};

        while(k > 0){
            k = (k-1)/2;
            if(dat[2*k+1].se && dat[2*k+2].se){
                dat[k] = {dat[2*k+1].fi+dat[2*k+2].fi, true};
            }else if(dat[2*k+2].se){
                dat[k] = {dat[2*k+1].fi+dat[2*k+2].fi, false};
            }else{
                dat[k] = {dat[2*k+2].fi, false};
            }
        }
    }

    // the minimun element of [a, b)
    ll query(ll a, ll b){return query_sub(a, b, 0, 0, n).fi;}

    pll query_sub(ll a, ll b, ll k, ll l, ll r){
        if(r <= a || b <= l){
            return {0, true};
        }else if(a <= l && r <= b){
            return dat[k];
        }else{
            pll vl = query_sub(a, b, 2*k+1, l, (l+r)/2);
            pll vr = query_sub(a, b, 2*k+2, (l+r)/2, r);
            if(vl.se && vr.se){
                return {vl.fi+vr.fi, true};
            }else if(vr.se){
                return {vl.fi+vr.fi, false};
            }else{
                return {vr.fi, false};
            }
        }
    }
};

int main(){
    ll n, q;
    cin >> n >> q;

    SegmentTree ST(n);
    rep(i, n){
        ll a;
        cin >> a;
        ST.update(i, a);
    }

    vector<char> ans;
    rep(i, q){
        ll t, x, y;
        cin >> t >> x >> y;

        if(t == 1){
            ST.update(x-1, y);
        }else{
            if(ST.query(x-1, y)%2 == 0){
                ans.pb('F');
            }else{
                ans.pb('S');
            }
        }
    }

    rep(i, (ll)ans.size()) cout << ans[i] << endl;
}