[UOJ35]后缀排序 做题笔记

题目链接：http://uoj.ac/problem/35
这也是个后缀数组的模板题。。。

#include <cstdio>#include <cstring>#include <algorithm>using namespace std;const int N=100009;char s[N];int r[N],wa[N],wb[N],wd[N],wv[N];int sa[N],rank[N],height[N];int 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=wa,*y=wb,*t;    for (i=0;i<m;i++) wd[i]=0;    for (i=0;i<n;i++) wd[x[i]=r[i]]++;    for (i=1;i<m;i++) wd[i]+=wd[i-1];    for (i=n-1;i>=0;i--) sa[--wd[x[i]]]=i;    for (j=1,p=1;p<n;j<<=1,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++) wd[i]=0;        for (i=0;i<n;i++) wd[wv[i]]++;        for (i=1;i<m;i++) wd[i]+=wd[i-1];        for (i=n-1;i>=0;i--) sa[--wd[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++;    }}void calheight (int *r,int *sa,int n) {    int i,j,k=0;    for (i=1;i<=n;i++) rank[sa[i]]=i;    for (i=0;i<n;height[rank[i++]]=k)         for (k?k--:0,j=sa[rank[i]-1];r[i+k]==r[j+k];k++);}int main () {    scanf("%s",s);    int n=strlen(s);    for (int i=0;i<n;i++) r[i]=s[i]-96;    r[n]=0;n++;    da(r,sa,n,40);    calheight(r,sa,n-1);    for (int i=1;i<n;i++) {        printf("%d ",sa[i]+1);    }    puts("");    for (int i=2;i<n;i++) {        printf("%d ",height[i]);    }}