refactor(字符串哈希): 重构字符串哈希实现并优化代码结构

将P3370.cpp从src/2移动到src/11/28目录并重构实现
新增P3375.cpp实现字符串匹配和回文前缀查找功能
使用更简洁的代码风格和更高效的哈希算法

src/11/28/P3370.cpp

@@ -0,0 +1,32 @@
+#include <cstdint>
+#include <iostream>
+#include <istream>
+#include <set>
+#include <string>
+using ll = int64_t;
+
+const ll b=233,p=1e9+7;
+
+ll n;
+std::string tmp;
+std::set<ll> s;
+
+static inline ll strhash(std::string &s){
+    ll res=0;
+    for(ll i=0;i<s.size();i++){
+        res=(res*b+s[i]-'0')%p;
+    }
+    return res;
+}
+
+int main(){
+    std::iostream::sync_with_stdio(false);
+    std::cin.tie(nullptr);
+
+    std::cin>>n;
+    for(ll i=1;i<=n;i++){
+        std::cin>>tmp;
+        s.emplace(strhash(tmp));
+    }
+    std::cout<<s.size()<<"\n";
+}

src/11/28/P3375.cpp

@@ -0,0 +1,76 @@
+#include <algorithm>
+#include <cstdint>
+#include <cstdio>
+#include <iostream>
+#include <istream>
+#include <string>
+#include <vector>
+using ll = int64_t;
+#define printf
+#define sl static inline
+
+const ll b=233,p=1e9+7;
+std::string s1,s2;
+ll n1,n2,h2;
+std::vector<ll> v1,bp,v2,v2r;
+
+sl ll strhash(std::string&s){
+    ll res=0;
+    for(ll i=0;i<s.size();i++){
+        res=(res*b+s[i])%p;
+    }
+    return res;
+}
+
+int main(){
+    std::iostream::sync_with_stdio(false);
+    std::cin.tie(nullptr);  
+
+    std::cin>>s1>>s2;
+    h2=strhash(s2);
+    n1=s1.size(),n2=s2.size();
+    s1=' '+s1;s2=' '+s2;
+    v1.resize(s1.size());
+    v2.resize(s2.size());
+    v2r.resize(s2.size()+1);
+    bp.resize(std::max(s1.size(),s2.size()));
+    bp[0]=1;
+    for(ll i=1;i<bp.size();i++){
+        bp[i]=(bp[i-1]*b)%p;
+    }
+
+    for(ll i=1;i<=n1;i++){
+        v1[i]=(v1[i-1]*b+s1[i])%p;
+        if(ll s=i-n2+1;s>=1){
+            ll h1=(v1[i]-v1[s-1]*bp[n2]%p+p)%p;
+            printf("v1=%lld, h1=%lld, h2=%lld\n",v1[i],h1,h2);
+            if(h1==h2){
+                std::cout<<s<<"\n";
+            }
+        }
+    }
+    for(ll i=1;i<=n2;i++){
+        v2[i]=(v2[i-1]*b+s2[i])%p;
+    }
+    for(ll i=n2;i>=1;i--){
+        v2r[i]=(v2r[i+1]*b+s2[i])%p;
+    }
+    for(ll i=1;i<=n2;i++){
+        ll l=1,r=i/2,ans=0,mid;
+        while(l<=r){
+            mid=(l+r)/2;
+            ll h1=v2[mid];
+            // ll h2=(v2[i]-v2[i-mid]*bp[mid]%p+p)%p;
+            ll h2=(v2r[i-mid+1]-v2r[i+1]*bp[mid]%p+p)%p;
+            printf("i=%lld, l=%lld, r=%lld, mid=%lld, h1=%lld, h2=%lld\n",i,l,r,mid,h1,h2);
+            if(h1==h2){
+                ans=mid;
+                l=mid+1;
+            }else{
+                r=mid-1;
+            }
+        }
+        std::cout<<ans<<" ";
+    }
+    std::cout<<"\n";
+}

src/2/P3370.cpp

@@ -1,38 +0,0 @@
-#include <algorithm>
-#include <cstdio>
-#include <cstring>
-#include <iostream>
-#include <istream>
-using namespace std;
-
-using ull= unsigned long long;
-
-ull base = 131;
-ull a[10010];
-char s[10010];
-int n, ans = 1;
-int prime = 233317;
-const ull mod = 212370440130137957ll;
-
-ull mhash(char *s) {
-  int len = strlen(s);
-  ull ans = 0;
-  for (int i = 0; i < len; i++)
-    ans = (ans * base + (ull)s[i]) % mod + prime;
-  return ans;
-}
-
-int main() {
-    iostream::sync_with_stdio(false);cin.tie(nullptr),cout.tie(nullptr);
-    cin >> n;
-    for (int i = 1; i <= n; i++) {
-        cin >> s;
-        a[i] = mhash(s);
-    }
-    sort(a + 1, a + n + 1);
-    for (int i = 1; i < n; i++) {
-        if (a[i] != a[i + 1])
-        ans++;
-    }
-    cout << ans << '\n';
-}