Add a lot more of my solutions.

I don't remember which ones doesn't pass though

CSES Problem Set/String Matching.cpp

@@ -0,0 +1,125 @@
+/* Problem URL: https://cses.fi/problemset/task/1753 */
+
+#include <bits/stdc++.h>
+#include <random>
+
+using namespace std;
+
+#define V vector
+
+#define rmin(a, b) a = min(a, b)
+#define rmax(a, b) a = max(a, b)
+
+#define rep(i, lim) for (size_t i = 0; i < (lim); i++)
+#define nrep(i, s, lim) for (size_t i = s; i < (lim); i++)
+
+#define repv(i, v) for (auto &i : (v))
+#define fillv(v) for (auto &itr_ : (v)) { cin >> itr_; }
+#define sortv(v) sort(v.begin(), v.end())
+#define all(v) (v).begin(), (v).end()
+
+using vi = vector<int>;
+using vvi = vector<vi>;
+using vvvi = vector<vvi>;
+using vvvvi = vector<vvvi>;
+
+using ll = long long;
+
+using vl = vector<ll>;
+using vvl = vector<vl>;
+using vvvl = vector<vvl>;
+using vvvvl = vector<vvvl>;
+
+template<class v>
+auto operator<<(ostream &os, const vector<v> &vec)->ostream& {
+    os << vec[0];
+    for (size_t i = 1; i < vec.size(); i++) {
+        os << ' ' << vec[i];
+    }
+    os << '\n';
+    return os;
+}
+
+template<class v>
+auto operator>>(istream &is, vector<v> &vec)->istream& {
+    for (auto &i : vec) {
+        is >> i;
+    }
+    return is;
+}
+
+template<class v>
+auto operator<<(ostream &os, const vector<vector<v>> &vec)->ostream& {
+    for (auto &i : vec) {
+        os << i[0];
+        for (size_t j = 1; j < i.size(); j++) {
+            os << ' ' << i[j];
+        }
+        os << '\n';
+    }
+    return os;
+}
+
+template<class v>
+auto operator>>(istream  &is, vector<vector<v>> &vec)->istream& {
+    for (auto &i : vec) {
+        for (auto &j : i) {
+            is >> j;
+        }
+    }
+    return is;
+}
+
+struct hash_string {
+    vl pow;
+    vl hash;
+    static ll base;
+    static ll mod;
+
+    hash_string() = delete;
+    hash_string(string &a) {
+        pow.resize(a.size() + 1);
+        hash.resize(a.size() + 1);
+
+        pow[0] = 1;
+        hash[0] = 0;
+
+
+        rep(i, a.size()) {
+            pow[i + 1] = ((__int128)pow[i] * base) % mod;
+            hash[i + 1] = ((__int128)hash[i] * base + a[i]) % mod;
+        }
+    }
+
+    ll gethash(int i, int f)
+    {
+        return ((hash[f + 1] - ((__int128)hash[i] * pow[f - i + 1])) % mod + mod) % mod;
+    }
+};
+
+ll hash_string::mod = (1LL << 61) - 1;
+mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
+ll hash_string::base = uniform_int_distribution<ll>(0, (1LL << 61) - 1)(rng);
+
+int main()
+{
+    ios::sync_with_stdio(false);
+    cin.tie(nullptr);
+
+    string a, b;
+    cin >> a >> b;
+
+    hash_string ahash(a);
+    hash_string bhash(b);
+
+    ll hash = bhash.gethash(0, b.size() - 1);
+
+    ll count = 0;
+    for (size_t i = 0; i + b.size() - 1 < a.size(); i++) {
+        if (hash == ahash.gethash(i, i + b.size() - 1)) {
+            count++;
+        }
+    }
+
+    cout << count << '\n';
+}