后缀数组

#include <iostream>  
#include <cstdlib>  
#include <cstring>  
#include <cstdio>  

using namespace std;  
const int N = 100000 + 11;  
int rank[N],wb[N],wv[N],wss[N],n;
int Sa[N],R[N];
int f[N],height[N];  



  
bool cmp(int *r,int a,int b,int l)
{
    return r[a] == r[b] && r[a+l] == r[b+l];
}

void da(int *r,int *sa,int n,int m)
{
    int i,j,p,*x = rank, *y = wb, *t;
    for(i = 0; i < m; ++i) wss[i] = 0;
    for(i = 0; i < n; ++i) ++wss[x[i]=r[i]];
    for(i = 1; i < m; ++i ) wss[i] += wss[i-1];
    for(i = n - 1; i >= 0; --i) sa[--wss[x[i]]] = i;    

    for(j = 1,p = 1; p < n; j *= 2, m = p)
    {
        for(p = 0,i = n - j; i < n; ++i) y[p++] = i;
        for(i = 0; i < n; ++i)if(sa[i] >= j)y[p++] = sa[i] - j;
        for(i = 0; i < n; ++i) wv[i] = x[y[i]];
        for(i = 0; i < m; ++i) wss[i] = 0;
        for(i = 0; i < n; ++i) ++wss[wv[i]];
        for(i = 1; i < m; ++i) wss[i] += wss[i-1];
        for(i = n - 1; i >= 0; --i) sa[--wss[wv[i]]] = y[i];
        for(t = x, x = y, y = t,p = 1, x[sa[0]] = 0, i = 1; i < n; ++i)
        x[sa[i]] = cmp(y,sa[i-1],sa[i],j)?p-1:p++;
        
    }    
  42 }

void cal_height(int *r,int *sa,int n)
{
    int i,j,k = 0;
    for(i = 1; i <= n; ++i) f[sa[i]] = i;
    for(i = 0; i < n; height[f[i++]] = k)
    for(k?k--:0,j = sa[f[i]-1] ;r[i+k] == r[j+k]; ++k);

}

char ss[N];  
int main()  
{  
    scanf("%s",ss);
    int l = strlen(ss);
    for(int i = 0; i < l; ++i) R[i] = ss[i]; R[l] = 0;
    da(R,Sa,l + 1,128);
    cal_height(R,Sa,l);

    return 0;
}