hdu 3068 Manacher算法

题意：求最长回文串，模板题

 #include<cstdio>
 #include<iostream>
 #include<algorithm>
 #include<cstring>
 #include<cmath>
 #include<queue>
 #include<map>
 using namespace std;
 #define MOD 1000000007
 const int INF=0x3f3f3f3f;
 const double eps=1e-;
 #define cl(a) memset(a,0,sizeof(a))
 #define ts printf("*****\n");
 int n,m,tt;const int MAXN=;
 char Ma[MAXN*];
 int Mp[MAXN*];
 void Manacher(char s[],int len)
 {
     int l=;
     Ma[l++]='$';
     Ma[l++]='#';
     for(int i=;i<len;i++)
     {
         Ma[l++]=s[i];
         Ma[l++]='#';
     }
     Ma[l]=;
     int mx=,id=;
     for(int i=;i<l;i++)
     {
         Mp[i]=mx>i?min(Mp[*id-i],mx-i):;
         while(Ma[i+Mp[i]]==Ma[i-Mp[i]])Mp[i]++;
         if(i+Mp[i]>mx)
         {
             mx=i+Mp[i];
             id=i;
         }
     }
 }
 char s[MAXN];
 int main()
 {
     #ifndef ONLINE_JUDGE
     freopen("1.in","r",stdin);
     #endif
     while(scanf("%s",s)==)
     {
         int len=strlen(s);
         Manacher(s,len);
         int ans=;
         for(int i=;i<*len+;i++)
         ans=max(ans,Mp[i]-);
         printf("%d\n",ans);
     }
     return ;
 }