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
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
#ifndef LOCAL
#pragma GCC optimize("O3")
#endif
#include <cstdio>
#include <cstring>
#include <vector>
#include <array>
#define FOR(i,p,k) for(int i=(p); i<=(k); ++i)
#define REP(i,k) FOR(i,0,(k)-1)
#define RFOR(i,p,n) for(int i=(p); i>=(n); --i)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define ssize(x) int((x).size())
#define fi first
#define se second
#define V vector
#define pb push_back
#define eb emplace_back
#define C const
#define pn printf("\n")
using namespace std;
typedef long long ll;
typedef V <int> vi;
typedef V <ll> vll;
typedef C int ci;
typedef C ll cll;
typedef pair <int, int> pii;
typedef pair <ll, ll> pll;
void chmin(auto &a, auto b){a=min(a,b);}
void chmax(auto &a, auto b){a=max(a,b);}
void chmax(short &a, int b){a=max(a,short(b));}
ci inf=2.1e9;
cll infll=4.5e18;
int I(){
    int z;
    scanf("%d", &z);
    //cin>>z;
    return z;
}
void ans(){
    ci n=I(),kcap=I(),t=I();
    scanf("\n");
    vi wej(n+1),pref(n+1);
    FOR(i, 1, n)
        wej[i]=getchar_unlocked()-'0',pref[i]=pref[i-1]+(wej[i]<3);
    short dp[n+1][kcap+2][3];
    //static short dp[8000+1][8000+2][3];
    memset(dp, 0x80, sizeof(dp));
    dp[0][0][0]=0;
    REP(i, n){
        // todo: może opt
        if (i+t<=n){
            ci kd=pref[i+t]-pref[i];
            ci cap=min(i, kcap-kd)+1;
            // wsiadamy i jedziemy
            REP(k, cap){
                // [0]
                chmax(dp[i+t][k+kd][1], dp[i][k][0]);
                // [1]
                chmax(dp[i+t][k+kd][2], dp[i][k][1]);
            }
        }
        ci cap=min(i, kcap)+1;
        if (wej[i+1]==1)
            REP(k, cap){
                // patyczkujemy
                chmax(dp[i+1][k+1][0], dp[i][k][0]+1);
                chmax(dp[i+1][k+1][2], dp[i][k][2]+1);
                // pracujemy
                chmax(dp[i+1][k][1], dp[i][k][1]);
            }
        if (wej[i+1]==2)
            REP(k, cap){
                // patyczkujemy
                chmax(dp[i+1][k+1][0], dp[i][k][0]+1);
                chmax(dp[i+1][k+1][2], dp[i][k][2]+1);
                // pracujemy
                chmax(dp[i+1][k][1], dp[i][k][1]);
                chmax(dp[i+1][k][0], dp[i][k][0]);
                chmax(dp[i+1][k][2], dp[i][k][2]);
            }
        if (wej[i+1]==3)
            REP(k, cap){
                // patyczkujemy
                chmax(dp[i+1][k][0], dp[i][k][0]+1);
                chmax(dp[i+1][k][2], dp[i][k][2]+1);
                // pracujemy
                chmax(dp[i+1][k][1], dp[i][k][1]);
            }
    }
    short w=-1;
    REP(k, kcap+1){
        chmax(w, dp[n][k][0]);
        chmax(w, dp[n][k][2]);
    }
    printf("%d\n", int(w));
}
int main(){
    //ios_base::sync_with_stdio(0),cin.tie(0);
    int tt=1;
    //tt=I();
    while (tt--)ans();
}