update

src/8/20/P2312.cpp

@@ -0,0 +1,88 @@
+#include <cctype>
+#include <iostream>
+#include <string>
+#include <vector>
+
+using i128 = __int128_t;
+using ll = int64_t;
+
+static ll n, m;
+static const ll mod = 1e9+7;
+static std::vector<std::vector<ll>> a;
+
+static inline constexpr ll strp(const std::string &s, ll p) {
+    ll num = 0;
+    int idx = 0;
+    ll nag = 1;
+    if (s[0] == '-') {
+        nag = -1;
+        idx = 1;
+    }
+    for (size_t i = idx; i < s.length(); ++i) {
+        num = (num * 10 + (s[i] - '0')) % p;
+    }
+    num = (num * nag) % p;
+    if (num < 0) {
+        num += p;
+    }
+    return num;
+}
+
+int main() {
+
+    std::ios_base::sync_with_stdio(false);
+    std::cin.tie(NULL);
+
+    std::cin >> n >> m;
+    a.resize(n + 1, std::vector<ll>(1));
+    for (int i = 0; i <= n; ++i) {
+        std::string tmpstr;
+        std::cin >> tmpstr;
+        for (size_t k = 0; k < 1; ++k) {
+            a[i][k] = strp(tmpstr,mod);
+        }
+    }
+
+    std::vector<ll> sol;
+    sol.reserve(100);
+
+    for (ll i = 1; i <= m; ++i) {
+        bool isok = true;
+        for (size_t k = 0; k < 1; ++k) {
+
+            const ll p = mod;
+            const auto &cur = a;
+
+            ll curx = 1;
+            i128 sum = 0;
+
+            for (int j = 0; j <= n; ++j) {
+
+                sum += (i128)cur[j][k] * curx;
+                curx = (curx * i) % p;
+
+                if ((j & 15) == 15) {
+                    sum %= p;
+                }
+            }
+
+            sum %= p;
+
+            if (sum != 0) {
+                isok = false;
+                break;
+            }
+        }
+
+        if (isok) {
+            sol.push_back(i);
+        }
+    }
+
+    std::cout << sol.size() << '\n';
+    for (ll ans : sol) {
+        std::cout << ans << '\n';
+    }
+
+    return 0;
+}

src/8/21/kmp.cpp

@@ -0,0 +1,72 @@
+#include <iostream>
+#include <string>
+#include <vector>
+
+std::vector<int> compute_next(const std::string &p) {
+    int m = p.length();
+    std::vector<int> next(m, 0);
+
+    for (int i = 1, j = 0; i < m; ++i) {
+
+        while (j > 0 && p[i] != p[j]) {
+            j = next[j - 1];
+        }
+
+        if (p[i] == p[j]) {
+            j++;
+        }
+
+        next[i] = j;
+    }
+
+    return next;
+}
+
+std::vector<int> kmp_search(const std::string &text, const std::string &p) {
+    int n = text.length();
+    int m = p.length();
+
+    if (m == 0)
+        return {};
+    if (n < m)
+        return {};
+
+    std::vector<int> next = compute_next(p);
+    std::vector<int> res;
+
+    for (int i = 0, j = 0; i < n; ++i) {
+        while (j > 0 && text[i] != p[j]) {
+            j = next[j - 1];
+        }
+        if (text[i] == p[j]) {
+            j++;
+        }
+        if (j == m) {
+            res.push_back(i - m + 1);
+            j = next[j - 1];
+        }
+    }
+    return res;
+}
+
+int main() {
+    std::string text = "ABABDABACDABABCABAB";
+    std::string p = "ABABCABAB";
+
+    std::cout << "Text:    " << text << std::endl;
+    std::cout << "p: " << p << std::endl;
+
+    std::vector<int> ans1 = kmp_search(text, p);
+
+    if (ans1.empty()) {
+        std::cout << "p not found " << std::endl;
+    } else {
+        std::cout << "p found at ";
+        for (size_t i = 0; i < ans1.size(); ++i) {
+            std::cout << ans1[i] << (i == ans1.size() - 1 ? "" : ", ");
+        }
+        std::cout << std::endl;
+    }
+
+    return 0;
+}