#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
const long long MOD = 998244353;
// using mint = modint1000000007;
// const long long MOD = 1000000007;
// using mint = modint;//mint::set_mod(MOD);

#include <bits/stdc++.h>
#define rep(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
#define repeq(i, a, b) for (ll i = (ll)(a); i <= (ll)(b); i++)
#define repreq(i, a, b) for (ll i = (ll)(a); i >= (ll)(b); i--)
#define endl '\n'  // fflush(stdout);
#define cYes cout << "Yes" << endl
#define cNo cout << "No" << endl
#define sortr(v) sort(v, greater<>())
#define pb push_back
#define pob pop_back
#define mp make_pair
#define mt make_tuple
#define FI first
#define SE second
#define ALL(v) (v).begin(), (v).end()
#define INFLL 3000000000000000100LL
#define INF 1000000100
#define PI acos(-1.0L)
#define TAU (PI * 2.0L)

using namespace std;

typedef long long ll;
typedef pair<ll, ll> Pll;
typedef tuple<ll, ll, ll> Tlll;
typedef vector<int> Vi;
typedef vector<Vi> VVi;
typedef vector<ll> Vl;
typedef vector<Vl> VVl;
typedef vector<VVl> VVVl;
typedef vector<Tlll> VTlll;
typedef vector<mint> Vm;
typedef vector<Vm> VVm;
typedef vector<string> Vs;
typedef vector<double> Vd;
typedef vector<char> Vc;
typedef vector<bool> Vb;
typedef vector<Pll> VPll;
typedef priority_queue<ll> PQl;
typedef priority_queue<ll, vector<ll>, greater<ll>> PQlr;

/* inout */
ostream &operator<<(ostream &os, mint const &m) {
    os << m.val();
    return os;
}
istream &operator>>(istream &is, mint &m) {
    long long n;
    is >> n, m = n;
    return is;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<T> &v) {
    int n = v.size();
    rep(i, 0, n) { os << v[i] << " \n"[i == n - 1]; }
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, const vector<vector<T>> &v) {
    int n = v.size();
    rep(i, 0, n) os << v[i];
    return os;
}
template <typename T, typename S>
ostream &operator<<(ostream &os, pair<T, S> const &p) {
    os << p.first << ' ' << p.second;
    return os;
}
template <typename T, typename S>
ostream &operator<<(ostream &os, const map<T, S> &ma) {
    for (auto &[key, val] : ma) {
        os << key << ':' << val << '\n';
    }
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, const set<T> &st) {
    auto itr = st.begin();
    for (int i = 0; i < (int)st.size(); i++) {
        os << *itr << (i + 1 != (int)st.size() ? ' ' : '\n');
        itr++;
    }
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, multiset<T> &st) {
    auto itr = st.begin();
    for (int i = 0; i < (int)st.size(); i++) {
        os << *itr << (i + 1 != (int)st.size() ? ' ' : '\n');
        itr++;
    }
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, queue<T> q) {
    while (q.size()) {
        os << q.front();
        q.pop();
        os << " \n"[q.empty()];
    }
    return os;
}
template <typename T>
ostream &operator<<(ostream &os, stack<T> st) {
    vector<T> v;
    while (st.size()) {
        v.push_back(st.top());
        st.pop();
    }
    reverse(ALL(v));
    os << v;
    return os;
}
template <class T, class Container, class Compare>
ostream &operator<<(ostream &os, priority_queue<T, Container, Compare> pq) {
    vector<T> v;
    while (pq.size()) {
        v.push_back(pq.top());
        pq.pop();
    }
    os << v;
    return os;
}
template <typename T>
istream &operator>>(istream &is, vector<T> &v) {
    for (T &in : v) is >> in;
    return is;
}
template <typename T1, typename T2>
istream &operator>>(istream &is, pair<T1, T2> &p) {
    is >> p.first >> p.second;
    return is;
}

/* useful */
template <typename T>
int SMALLER(vector<T> &a, T x) {
    return lower_bound(a.begin(), a.end(), x) - a.begin();
}
template <typename T>
int orSMALLER(vector<T> &a, T x) {
    return upper_bound(a.begin(), a.end(), x) - a.begin();
}
template <typename T>
int BIGGER(vector<T> &a, T x) {
    return a.size() - orSMALLER(a, x);
}
template <typename T>
int orBIGGER(vector<T> &a, T x) {
    return a.size() - SMALLER(a, x);
}
template <typename T>
int COUNT(vector<T> &a, T x) {
    return upper_bound(ALL(a), x) - lower_bound(ALL(a), x);
}
template <typename T, typename S>
bool chmax(T &a, S b) {
    if (a < b) {
        a = b;
        return 1;
    }
    return 0;
}
template <typename T, typename S>
bool chmin(T &a, S b) {
    if (a > b) {
        a = b;
        return 1;
    }
    return 0;
}
template <typename T>
void press(T &v) {
    v.erase(unique(ALL(v)), v.end());
}
template <typename T>
vector<int> zip(vector<T> a) {
    int n = a.size();
    pair<T, int> p[n];
    vector<int> v(n);
    for (int i = 0; i < n; i++) p[i] = make_pair(a[i], i);
    sort(p, p + n);
    int w = 0;
    for (int i = 0; i < n; i++) {
        if (i && p[i].first != p[i - 1].first) w++;
        v[p[i].second] = w;
    }
    return v;
}
template <typename T>
vector<T> vis(vector<T> &v) {
    vector<T> S(v.size() + 1);
    rep(i, 1, S.size()) S[i] += v[i - 1] + S[i - 1];
    return S;
}
template <typename T>
T ceil_div(T a, T b) {
    if (b < 0) a = -a, b = -b;
    return (a >= 0 ? (a + b - 1) / b : a / b);
}
template <typename T>
T floor_div(T a, T b) {
    if (b < 0) a = -a, b = -b;
    return (a >= 0 ? a / b : (a - b + 1) / b);
}
ll dtoll(double d, int g) { return round(d * pow(10, g)); }

const double EPS = 1e-10;

void init() {
    cin.tie(0);
    cout.tie(0);
    ios::sync_with_stdio(0);
    cout << fixed << setprecision(12);
}

// do {} while (next_permutation(ALL(vec)));

/********************************** START **********************************/

void sol();

int main() {
    init();
    int q = 1;
    // cin >> q;
    while (q--) sol();
    return 0;
}

/********************************** SOLVE **********************************/

struct RollingHash {
    int n;
    static const ll base1 = 1009;
    static const ll base2 = 2009;
    static const ll mod1 = 1000000007;
    static const ll mod2 = 1000000009;
    vector<ll> hash1, hash2, pow1, pow2;

    RollingHash() {}
    RollingHash(const string &S) {
        n = (int)S.size();
        hash1.assign(n + 1, 0);
        hash2.assign(n + 1, 0);
        pow1.assign(n + 1, 1);
        pow2.assign(n + 1, 1);
        for (int i = 0; i < n; ++i) {
            hash1[i + 1] = (hash1[i] * base1 + S[i]) % mod1;
            hash2[i + 1] = (hash2[i] * base2 + S[i]) % mod2;
            pow1[i + 1] = (pow1[i] * base1) % mod1;
            pow2[i + 1] = (pow2[i] * base2) % mod2;
        }
    }

    /**
     * S の [l, r) のハッシュ値を返す
     * O(1)
     */
    inline pair<ll, ll> get(int l, int r) const {
        ll res1 = hash1[r] - hash1[l] * pow1[r - l] % mod1;
        if (res1 < 0) res1 += mod1;
        ll res2 = hash2[r] - hash2[l] * pow2[r - l] % mod2;
        if (res2 < 0) res2 += mod2;
        return make_pair(res1, res2);
    }

    /**
     * S のハッシュ値を返す
     * O(1)
     */
    inline pair<ll, ll> hash() const { return get(0, (int)hash1.size() - 1); }

    /**
     * LCP (Longest Common Prefix)
     * O( log N )
     */
    inline int getLCP(int a, int b) const {
        int len = min((int)hash1.size() - a, (int)hash1.size() - b);
        int low = 0, high = len;
        while (high - low > 1) {
            int mid = (low + high) >> 1;
            if (get(a, a + mid) != get(b, b + mid))
                high = mid;
            else
                low = mid;
        }
        return low;
    }

    /**
     * hash h1 と 長さ h2_len の文字列の hash h2 を結合
     */
    pair<ll, ll> concat(pair<ll, ll> h1, pair<ll, ll> h2, ll h2_len) {
        if (h2_len < pow1.size())
            return make_pair((h1.first * pow1[h2_len] + h2.first) % mod1,
                             (h1.second * pow2[h2_len] + h2.second) % mod2);
        return make_pair(
            (h1.first * pow_mod(base1, h2_len + 1, mod1) + h2.first) % mod1,
            (h1.second * pow_mod(base2, h2_len + 1, mod2) + h2.second) % mod2);
    }

    /**
     * 文字列の最小周期を返す
     */
    int max_repeat(bool multiple_only = false) {
        for (int i = 1; i < n; i++) {
            if (multiple_only && n % i != 0) continue;
            if (n - i < i) break;
            if (get(0, n - i) == get(i, n)) {
                return i;
            }
        }
        return n;
    }

    /**
     * hash h を count 回結合 (WIP)
     */
    pair<ll, ll> times(pair<ll, ll> h, ll len, ll count) {
        pair<ll, ll> ret = {0, 0}, now = h;
        ll pw = 1;
        while (count) {
            if (count & 1) ret = concat(ret, now, len * pw);
            now = concat(now, now, len * pw);
            count >>= 1;
            pw <<= 1;
        }
        return ret;
    }
};

template <typename T>
vector<T> convolution_rev(vector<T> a, vector<T> b) {
    int n = a.size();
    int m = b.size();
    reverse(ALL(b));
    auto v = convolution(a, b);
    vector<T> ret(n - m + 1);
    rep(i, 0, n - m + 1) ret[i] = v[i + m - 1];
    return ret;
}

void sol() {
    int n, m, k;
    string s, t;
    cin >> n >> m >> k >> s >> t;
    string sb = s, tb = t;
    rep(i, 0, sb.size()) sb[i] = toupper(sb[i]);
    rep(i, 0, tb.size()) tb[i] = toupper(tb[i]);
    RollingHash rs(s), rt(t), rsb(sb), rtb(tb);
    Vi cnt(n - m + 1, 0);
    rep(i, 0, 52) {
        char c = (i < 26 ? 'a' + i : 'A' + i - 26);
        char C = (i < 26 ? 'A' + i : 'a' + i - 26);
        vector<int> a(n), b(m);
        rep(j, 0, n) {
            if (s[j] == c)
                a[j] = 1;
            else
                a[j] = 0;
        }
        rep(i, 0, m) {
            if (t[i] == C)
                b[i] = 1;
            else
                b[i] = 0;
        }
        auto v = convolution_rev(a, b);
        rep(j, 0, n - m + 1) cnt[j] += v[j];
    }
    set<pair<ll, ll>> st;
    int ans = 0;
    rep(i, 0, n - m + 1) {
        if (rsb.get(i, i + m) == rtb.get(0, m) && cnt[i] > 0 && cnt[i] <= k) {
            ans++;
        }
    }
    cout << ans << endl;
}