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
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
#include <iostream>
#include <string>
#include <algorithm>


using namespace std;


static const int16_t UNK = -2;


static int n, k, t;
static string s;

static int aMeetingAggregatedCnt[8002];

static int16_t aDP[3][8192][8192];


static int RecursiveAtHome(int iLevel, int iHowManyICanSkip, bool fWasInTheOffice);
static int RecursiveInTheOffice(int iLevel, int iHowManyICanSkip);


static void InitDP()
{
    for (int i = 0; i < 3; ++i)
    {
        for (int j = 0; j < n; ++j)
        {
            for (int m = 0; m <= k; ++m)
            {
                aDP[i][j][m] = UNK;
            }
        }
    }
}


static void InitMeetingAggregatedCnt()
{
    for (int i = 0; i < n; ++i)
    {
        if (i == 0)
        {
            aMeetingAggregatedCnt[i] = 0;
        }
        else
        {
            aMeetingAggregatedCnt[i] = aMeetingAggregatedCnt[i - 1];
        }

        if (s[i] != '3')
        {
            aMeetingAggregatedCnt[i]++;
        }
    }
}


static inline int GetMeetingsDuringCommute(int iLevel)
{
    if (iLevel - t < 0)
    {
        return aMeetingAggregatedCnt[iLevel];
    }

    return aMeetingAggregatedCnt[iLevel] - aMeetingAggregatedCnt[iLevel - t];
}


static inline void AppendResult(int16_t & iRet, int iResult)
{
    if (iResult > iRet)
    {
        iRet = iResult;
    }
}


static inline void AppendResultIncremented(int16_t & iRet, int iResult)
{
    if (iResult == -1)
        return;

    iResult++;

    if (iResult > iRet)
    {
        iRet = iResult;
    }
}


static int RecursiveAtHome(int iLevel, int iHowManyICanSkip, bool fWasInTheOffice)
{
    if (iLevel == -1)     // fajrant
    {
        return 0;
    }

    int i = fWasInTheOffice ? 1 : 0;

    int16_t & iResult = aDP[i][iLevel][iHowManyICanSkip];

    if (iResult != UNK)
        return iResult;

    int iRemainingSlots = iLevel + 1;

    if (iHowManyICanSkip >= iRemainingSlots)
    {
        return iResult = iRemainingSlots;
    }

    int16_t iRet = -1;

    char c = s[iLevel];

    if (c == '1' && iHowManyICanSkip > 0)   // office meeting
    {
        AppendResultIncremented(iRet, RecursiveAtHome(iLevel - 1, iHowManyICanSkip - 1, fWasInTheOffice));   // skip office meeting and solve
    }

    if (c == '2')                           // remote meeting
    {
        AppendResult(iRet, RecursiveAtHome(iLevel - 1, iHowManyICanSkip, fWasInTheOffice));   // take part in remote meeting

        if (iHowManyICanSkip > 0)
            AppendResultIncremented(iRet, RecursiveAtHome(iLevel - 1, iHowManyICanSkip - 1, fWasInTheOffice));   // skip remote meeting and solve
    }

    if (c == '3')                           // no duties
    {
        AppendResultIncremented(iRet, RecursiveAtHome(iLevel - 1, iHowManyICanSkip, fWasInTheOffice));  // solve safely
    }

    if (!fWasInTheOffice && iRemainingSlots > t * 2)
    {
        int iMeetingsDuringCommute = GetMeetingsDuringCommute(iLevel);

        if (iHowManyICanSkip >= iMeetingsDuringCommute)
        {
            AppendResult(iRet, RecursiveInTheOffice(iLevel - t, iHowManyICanSkip - iMeetingsDuringCommute));   // go to the office
        }
    }

    return iResult = iRet;
}


static int RecursiveInTheOffice(int iLevel, int iHowManyICanSkip)
{
    int16_t & iResult = aDP[2][iLevel][iHowManyICanSkip];

    if (iResult != UNK)
        return iResult;

    int iRemainingSlots = iLevel + 1;

    if (iRemainingSlots < t)
        return iResult = -1;

    int16_t iRet = -1;

    int iMeetingsDuringCommute = GetMeetingsDuringCommute(iLevel);

    if (iHowManyICanSkip >= iMeetingsDuringCommute)
    {
        AppendResult(iRet, RecursiveAtHome(iLevel - t, iHowManyICanSkip - iMeetingsDuringCommute, true));   // go back home
    }

    if (iRemainingSlots == t)
    {
        return iResult = iRet;
    }

    char c = s[iLevel];

    if (c == '1')   // office meeting
    {
        AppendResult(iRet, RecursiveInTheOffice(iLevel - 1, iHowManyICanSkip));   // take part in office meeting

        if (iHowManyICanSkip > 0)
            AppendResultIncremented(iRet, RecursiveInTheOffice(iLevel - 1, iHowManyICanSkip - 1));   // skip office meeting and solve
    }

    if (c == '2')                           // remote meeting
    {
        AppendResult(iRet, RecursiveInTheOffice(iLevel - 1, iHowManyICanSkip));   // take part in remote meeting

        if (iHowManyICanSkip > 0)
            AppendResultIncremented(iRet, RecursiveInTheOffice(iLevel - 1, iHowManyICanSkip - 1));   // skip remote meeting and solve
    }

    if (c == '3')                           // no meetings
    {
        AppendResult(iRet, RecursiveInTheOffice(iLevel - 1, iHowManyICanSkip));  // do your job
    }

    return iResult = iRet;
}


int main()
{
    cin >> n >> k >> t >> s;

    InitDP();

    InitMeetingAggregatedCnt();

    int iAnswer = RecursiveAtHome(n - 1, k, false);

    cout << iAnswer;
}