/* main code starts from line 155. */

/* ---------- STL Libraries ---------- */

// IO library
#include <cstdio>
#include <iomanip>
#include <ios>
#include <iostream>

// algorithm library
#include <algorithm>
#include <cmath>
#include <numeric>

// container library
#include <array>
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <vector>

/* ---------- Namespace ---------- */

using namespace std;

/* ---------- Type Abbreviation ---------- */

template <typename T>
using V = vector<T>;
template <typename T, typename U>
using P = pair<T, U>;
template <typename T>
using PQ = priority_queue<T>;
template <typename T>
using GPQ = priority_queue<T, vector<T>, greater<T>>;

using ll = long long;

#define fst first
#define snd second
#define pb push_back
#define mp make_pair
#define mt make_tuple

/* ---------- conversion ---------- */

#define INT(c) static_cast<int>(c)
#define CHAR(n) static_cast<char>(n)
#define LL(n) static_cast<ll>(n)
#define DOUBLE(n) static_cast<double>(n)

/* ---------- container ---------- */

#define ALL(v) (v).begin(), (v).end()
#define SIZE(v) (LL((v).size()))

#define FIND(v, k) (v).find(k) != (v).end()
#define VFIND(v, k) find(ALL(v), k) != (v).end()

#define SORT(v) sort(ALL(v))
#define GSORT(v) sort(ALL(v), greater<decltype((v).front())>())

/* ---------- repetition ---------- */

#define FOR(i, a, b) for (ll i = (a); i <= (b); i++)
#define RFOR(i, a, b) for (ll i = (a); i >= (b); i--)

/* ---------- Short Functions ---------- */

template <typename T>
T sq(T a) {
    return a * a;
}

template <typename T>
T gcd(T a, T b) {
    if (a > b) return gcd(b, a);
    return a == 0 ? b : gcd(b % a, a);
}

template <typename T>
T mypow(T b, T n) {
    if (n == 0) return 1;
    if (n == 1) return n;
    if (n % 2 == 0) {
        return mypow(sq(b), n / 2);
    } else {
        return mypow(b, n - 1) * b;
    }
}

/* --------------------
template <typename T>
T mypow(T b, T n) {
    if (n == 0) return 1;
    if (n == 1) return n % MOD;
    if (n % 2 == 0) {
        return mypow(sq(b) % MOD, n / 2);
    } else {
        return mypow(b, n - 1) * b % MOD;
    }
}
-------------------- */

#define fcout cout << fixed << setprecision(10)

/* ----------- debug ---------- */

template <typename T, typename U>
void testP2(T a, U b) {
    cout << "(" << a << ", " << b << ")" << endl;
    return;
}

template <typename T>
void testV(T v) {
    cout << "[";
    for (auto i : v) {
        cout << i << ", ";
    }
    cout << "\b\b]" << endl;
    return;
}

template <typename T>
void testV2(T v) {
    for (auto sv : v) {
        testV(sv);
    }
    cout << endl;
    return;
}

#define GET_VAR_NAME(variable) #variable
#define test(x) cout << GET_VAR_NAME(x) << " = " << x << endl;
#define testP(p)                      \
    cout << GET_VAR_NAME(p) << " = "; \
    testP2(p.fst, p.snd);

/* ---------- Constants ---------- */

// const ll MOD = 1e9 + 7;
// const int INF = 1 << 25;
// const ll INF = 1LL << 50;
// const double PI = acos(-1);
// const double EPS = 1e-10;
// const ll dx[4] = {0, -1, 1, 0};
// const ll dy[4] = {-1, 0, 0, 1};
// const ll dx[8] = {-1, 0, 1, -1, 1, -1, 0, 1};
// const ll dy[8] = {-1, -1, -1, 0, 0, 1, 1, 1};

/* v-v-v-v-v-v-v-v-v Main Part v-v-v-v-v-v-v-v-v */

/* ---------- Type Definition ----------- */


/* ---------- Global Variance ----------- */

ll H, W, N;

/* ------------- Functions -------------- */

V<string> fall(V<string> S) {
    while (true) {
        auto pre = S;

        RFOR(x, H - 1, 1) {
            RFOR(y, W - 1, 0) {
                if (S[x][y] == '.') {
                    swap(S[x][y], S[x - 1][y]);
                }
            }
        }

        if (pre == S) break;
    }

    return S;
}


V<string> erase(V<string> S) {
    auto ret = S;
    FOR(x, 0, H - 1) {
        FOR(y, 0, W - 1) {
            if (S[x][y] == '.') continue;

            FOR(i, 0, 1) {
                ll dx = i, dy = 1 - i;
                ll cnt = 1;
                FOR(d, 1, 100) {
                    ll nx = x + dx * d;
                    ll ny = y + dy * d;
                    if (nx < 0 || nx >= H || ny < 0 || ny >= W || S[nx][ny] != S[x][y]) break;
                    cnt++;
                }

                if (cnt >= N) {
                    FOR(d, 0, cnt - 1) {
                        ll nx = x + dx * d;
                        ll ny = y + dy * d;
                        ret[nx][ny] = '.';
                    }
                }
            }
        }
    }

    return ret;
}

bool solve(ll x, ll y, V<string> S) {
    swap(S[x][y], S[x][y + 1]);

    while (true) {
        auto pre = S;
        S = erase(fall(S));
        if (pre == S) break;
    }

    /*
    testP2(x, y);
    FOR(i, 0, H - 1) {
        cout << S[i] << endl;
    }
    cout << "++++++++++" << endl;
    */

    FOR(i, 0, H - 1) {
        FOR(j, 0, W - 1) {
            if (S[i][j] != '.') {
                return false;
            }
        }
    }

    return true;
}

/* ----------- Main Function ------------ */

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    cin >> H >> W >> N;

    V<string> S(H);
    FOR(i, 0, H - 1) {
        cin >> S[i];
    }

    FOR(x, 0, H - 1) {
        FOR(y, 0, W - 2) {
            if (solve(x, y, S)) {
                cout << "YES" << endl;
                return 0;
            }
        }
    }

    cout << "NO" << endl;
    return 0;
}



Measured memory_bytes: 3252