1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
#include <bits/stdc++.h>

using namespace std;

#define _DEBUG
#ifdef _DEBUG
template<typename T1, typename T2> auto& operator<<(ostream& o, pair<T1, T2> a) { return o << "(" << a.first << ", " << a.second << ")"; }
template<typename T, typename OS> auto& operator<<(OS& o, T a) { o << "{"; for (auto b : a) o << b << ", "; return o << "}"; }
#define dbg(x...) cerr << "[" #x "]: ", [](auto... args) { ((cerr << args << ", "),...) << "\n"; }(x)
#else
#define dbg(...)
#endif

#define sz(x) ((int)(x).size())
#define all(x) (x).begin(), (x).end()
#define F first
#define S second

using ll = long long;
using ld = long double;
using pll = pair<ll, ll>;
using vi = vector<int>;

int main() {
    ios::sync_with_stdio(false); cin.tie(nullptr);

    ll n, k, t, ans = -1;
    cin >> n >> k >> t;
    string v; cin >> v;
    vector<ll> p1(n+1), p2(n+1), p3(n+1);
    for(ll i = 1 ; i <= n ; ++i) {
        p1[i] = p1[i-1]; p2[i] = p2[i-1]; p3[i] = p3[i-1];
        if(v[i-1] == '1') p1[i]++;
        if(v[i-1] == '2') p2[i]++;
        if(v[i-1] == '3') p3[i]++;
    }

    if(p1[n] <= k) {
        ans = p3[n]+min(k, p1[n]+p2[n]);
    } else {
        for(ll len = 2*t+1 ; len <= n ; ++len) {
            for(ll l1 = 1 ; l1+len-1 <= n ; ++l1) {
                ll r1 = l1+t-1, l2 = l1+len-t, r2 = l1+len-1;

                ll cnt = p1[n] - p1[l2-1] + p1[r1] +
                    p2[r2] - p2[l2-1] +
                    p2[r1] - p2[l1-1];

                ll re1 = p1[n] - p1[r2] + p1[l1-1];
                ll re2 = p2[n] - p2[r2] + p2[l1-1];
                ll re3 = p3[n] - p3[r2] + p3[l1-1];

                if(cnt <= k) {
                    ans = max(ans, re3 + re1 + min(k-cnt, re2));
                }
            }
        }
    }
    cout << ans;

    return 0;
}