말 라 차 알고리즘

       s,t 
  ：s，t            l，         r
           l==r，      
          l

             ：
    1.     ： s     
    2.l==r,  
    3.l

#include
using namespace std;
typedef long long ll;
const int maxn=5e6+5;
int p[maxn];
ll ans;
char s[maxn];
char snew[maxn];
int init(){
    int len=strlen(s),j=2;
    snew[0]='$',snew[1]='#';
    for(int i=0;ii)p[i]=min(p[2*id-i],mx-i);
        else p[i]=1;
        while(snew[i-p[i]]==snew[i+p[i]])///i-p[i]     , string    ,char[]  
            p[i]++;
        if(mx=0;--i)
            if(s1[i]!=s2[i])
            {
                r=i;
                break;
            }
        if(l==r)
            printf("0
");
        else if(l>r){
            strcpy(s,s1);
            printf("%lld
",manacher());
        }
        else if(l=0&&j

#include 
#include 
#include 
using namespace std;
string Manacher(string s)
{
    // Insert '#'
    string t = "$#";
    for (int i = 0; i < s.size(); ++i)
    {
        t += s[i];
        t += "#";
    }
    // Process t
    vector p(t.size(), 0);///     2   
    int mx = 0, id = 0, resLen = 0, resCenter = 0;
    for (int i = 1; i < t.size(); ++i)  /// 1  
    {
        p[i] = mx > i ? min(p[2 * id - i], mx - i) : 1;
        while (t[i + p[i]] == t[i - p[i]]) ++p[i];
        if (mx < i + p[i])
        {
            mx = i + p[i];
            id = i;
        }
        if (resLen < p[i])  ///    p[i]
        {
            resLen = p[i];///         
            resCenter = i;///         
        }
    }
    ///        len=resLen - 1;
    ///   (resCenter - resLen) / 2
    return s.substr((resCenter - resLen) / 2, resLen - 1);
}
int main()
{
    int n;
    cin>>n;
    string k;
    while(n--)
    {
        cin>>k;
        cout<