POJ 2774 Long long Message (suffix array entry)

1 /******************************************************************2 title: Long Long Message (POJ 2774)3 Links:http://poj.org/problem?id=27744 Test instructions: Give two strings, find the longest common substring5 algorithm: suffix array6 algorithm idea: suffix array is the set template to get the first deserved array, this problem uses two arrays, divided7 Sa[],height[];sa[i] Indicates that all suffixes are sorted by dictionary number to s[i]8 The beginning suffix is ranked in the first position. Height[i] Indicates the number of dictionaries for the I and i+1 suffixes9 The longest string of prefixes. Ten *******************************************************************/ One#include <cstdio> A#include <cstring> -#include <algorithm> - using namespacestd; the  - Const intmx=200100; - CharST[MX]; - intS[mx],sa[mx],t[mx],t2[mx],c[mx],n; + intRANK[MX],HEIGHT[MX]; -  + voidBuild_sa (intm) A { at     inti,*x=t,*y=T2; -      for(i=0; i<m;i++) c[i]=0; -      for(i=0; i<n;i++) c[x[i]=s[i]]++; -      for(i=1; i<m;i++) c[i]+=c[i-1]; -      for(i=n-1; i>=0; i--) sa[--c[x[i]]]=i; -      for(intk=1; k<=n;k<<=1) in     { -         intp=0; to          for(i=n-k;i<n;i++) y[p++]=i; +          for(i=0; i<n;i++)if(sa[i]>=k) y[p++]=sa[i]-K; -          for(i=0; i<m;i++) c[i]=0; the          for(i=0; i<n;i++) c[x[y[i]]]++; *          for(i=1; i<m;i++) c[i]+=c[i-1]; $          for(i=n-1; i>=0; i--) sa[--c[x[y[i]]]]=Y[i];Panax Notoginseng swap (x, y); -p=1; thex[sa[0]]=0; +          for(i=1; i<n;i++) Ax[sa[i]]=y[sa[i-1]]==y[sa[i]]&&y[sa[i-1]+k]==y[sa[i]+k]?p-1:p + +; the         if(p>=n) Break; +m=p; -     } $ } $  - voidgetheight () - { the     inti,j,k=0; -      for(i=0; i<n;i++) rank[sa[i]]=i;Wuyi      for(i=0; i<n-1; i++) the     { -         if(k) k--; Wu         intj=sa[rank[i]-1]; -          while(S[i+k]==s[j+k]) k++; Aboutheight[rank[i]]=K; $     } - } -  - intMain () A { +n=0; the     intL1,l2; -scanf"%s", ST); $l1=strlen (ST); the      for(intI=0; i<l1;i++) s[n++]=st[i]-'a'+1; thes[n++]= -; thescanf"%s", ST); theL2=strlen (ST); -      for(intI=0; i<l2;i++) s[n++]=st[i]-'a'+1; ins[n++]=0; theBuild_sa ( -); the getheight (); About     intmaxx=0; the      for(intI=2; i<n;i++) the     { the         if(maxx<Height[i]) +         { -             if(sa[i]>=0&&sa[i]<l1&&sa[i-1]>L1) themaxx=Height[i];Bayi             if(sa[i-1]>=0&&sa[i-1]<l1&&sa[i]>L1) themaxx=Height[i]; the         } -     } -printf"%d\n", Maxx); the     return 0; the}

POJ 2774 Long long Message (suffix array entry)