string/zalgorithm.cpp

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• Last update: 2021-03-04 17:00:41+09:00

Required by

• string/run.cpp

Verified with

• test/aoj/3081.test.cpp
• test/yosupo/runenumerate.test.cpp
• test/yosupo/zalgorithm.test.cpp

Code

#ifndef call_from_test
#include <bits/stdc++.h>
using namespace std;
#endif
//BEGIN CUT HERE
// longest common prefix of s and s[i:n]
// return n + 1 elements for run enumerate
template<typename T>
vector<int> zalgorithm(vector<T> vs){
  int n=vs.size();
  vector<int> as(n+1,0);
  as[0]=n;
  int i=1,j=0;
  while(i<n){
    while(i+j<n and vs[j]==vs[i+j]) j++;
    as[i]=j;
    if(j==0){
      i++;
      continue;
    }
    int k=1;
    while(i+k<n and k+as[k]<j) as[i+k]=as[k],k++;
    i+=k;
    j-=k;
  }
  return as;
}
vector<int> zalgorithm(string s){
  return zalgorithm(vector<char>(s.begin(),s.end()));
}
//END CUT HERE
#ifndef call_from_test
signed main(){
  return 0;
}
#endif

#line 1 "string/zalgorithm.cpp"

#include <bits/stdc++.h>
using namespace std;
#endif
//BEGIN CUT HERE
// longest common prefix of s and s[i:n]
// return n + 1 elements for run enumerate
template<typename T>
vector<int> zalgorithm(vector<T> vs){
  int n=vs.size();
  vector<int> as(n+1,0);
  as[0]=n;
  int i=1,j=0;
  while(i<n){
    while(i+j<n and vs[j]==vs[i+j]) j++;
    as[i]=j;
    if(j==0){
      i++;
      continue;
    }
    int k=1;
    while(i+k<n and k+as[k]<j) as[i+k]=as[k],k++;
    i+=k;
    j-=k;
  }
  return as;
}
vector<int> zalgorithm(string s){
  return zalgorithm(vector<char>(s.begin(),s.end()));
}
//END CUT HERE
#ifndef call_from_test
signed main(){
  return 0;
}
#endif

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