HDU3948 & 回文树模板

Description:

  求本质不同回文子串的个数

Solution:

  回文树模板,学一学贴一贴啊...

Code:

  

/*=================================
# Created time: 2016-04-20 20:55
# Filename: hdu3948.cpp
# Description: 
=================================*/
#define me AcrossTheSky&HalfSummer11  
#include <cstdio>  
#include <cmath>  
#include <ctime>  
#include <string>  
#include <cstring>  
#include <cstdlib>  
#include <iostream>  
#include <algorithm>  
  
#include <set> 
#include <stack>  
#include <queue>  
#include <vector>  
  
#define lowbit(x) (x)&(-x)  
#define Abs(x) ((x) > 0 ? (x) : (-(x)))  
#define FOR(i,a,b) for((i)=(a);(i)<=(b);(i)++)  
#define FORP(i,a,b) for(int i=(a);i<=(b);i++)  
#define FORM(i,a,b) for(int i=(a);i>=(b);i--)  
#define ls(a,b) (((a)+(b)) << 1)  
#define rs(a,b) (((a)+(b)) >> 1)  
#define getlc(a) ch[(a)][0]  
#define getrc(a) ch[(a)][1]  
  
#define maxn 100005 
#define maxc 30
#define maxm 100005 
#define INF 1070000000  
using namespace std;  
typedef long long ll;  
typedef unsigned long long ull;  
  
template<class T> inline  
void read(T& num){  
    num = 0; bool f = true;char ch = getchar();  
    while(ch < '0' || ch > '9') { if(ch == '-') f = false;ch = getchar();}  
    while(ch >= '0' && ch <= '9') {num = num * 10 + ch - '0';ch = getchar();}  
    num = f ? num: -num;  
} 
int outs[100]; 
template<class T> inline 
void write(T x){ 
	if (x==0) {putchar('0'); putchar('
'); return;} 
	if (x<0) {putchar('-'); x=-x;} 
	int num=0; 
	while (x){ outs[num++]=(x%10); x=x/10;} 
	FORM(i,num-1,0) putchar(outs[i]+'0'); putchar('
'); 
} 
/*==================split line==================*/ 
int tot[maxn],num[maxn],len[maxn],fail[maxn],S[maxn],ch[maxn][maxc];
char s[maxn];
int p,last,ans,cnt;
int newnode(int l){
	tot[p]=0; num[p]=0; len[p]=l;
	return p++;
}
void init(){
	p=0; memset(ch,0,sizeof(ch));
	newnode(0); newnode(-1);
	last=0; cnt=0; S[cnt]=-1; fail[0]=1;
}
int get_fail(int x){
	while(S[cnt-len[x]-1]!=S[cnt]) x=fail[x];
	return x;
}
void add(int c,int pos){
	S[++cnt]=c;
	int cur=get_fail(last);
	if (!ch[cur][c]){
		int now=newnode(len[cur]+2);
		fail[now]=ch[get_fail(fail[cur])][c];
		ch[cur][c]=now; ans++;
	}
	last=ch[cur][c];
	tot[last]++;
}
int main(){
	int cas; read(cas); int Cas=1;
	while (Cas<=cas){
		printf("Case #%d: ",Cas);
		ans=0;
		scanf("%s",s);
		int n=strlen(s);
		init();
		FORP(i,0,n-1) add(s[i]-'a'+1,i);
		write(ans); 
		Cas++;
	}
}
原文地址:https://www.cnblogs.com/YCuangWhen/p/5414496.html