datastructure/sparsetable.cpp

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• Last update: 2020-10-27 19:32:25+09:00

Verified with

• test/aoj/3086.test.cpp
• test/aoj/DSL_3_D.sparsetable.test.cpp
• test/yosupo/staticrmq.sparsetable.test.cpp

Code

#ifndef call_from_test
#include <bits/stdc++.h>
using namespace std;
#endif
//BEGIN CUT HERE
template<typename T>
struct SparseTable{
  using F = function<T(T, T)>;
  vector< vector<T> > dat;
  vector<int> ht;
  const F f;

  SparseTable(F f):f(f){}

  void build(const vector<T> &v){
    int n=v.size(),h=1;
    while((1<<h)<=n) h++;
    dat.assign(h,vector<T>(n));
    ht.assign(n+1,0);
    for(int j=2;j<=n;j++) ht[j]=ht[j>>1]+1;

    for(int j=0;j<n;j++) dat[0][j]=v[j];
    for(int i=1,p=1;i<h;i++,p<<=1)
      for(int j=0;j<n;j++)
        dat[i][j]=f(dat[i-1][j],dat[i-1][min(j+p,n-1)]);
  };

  T query(int a,int b){
    int l=b-a;
    return f(dat[ht[l]][a],dat[ht[l]][b-(1<<ht[l])]);
  }
};
//END CUT HERE
#ifndef call_from_test
signed main(){
  return 0;
}
#endif

#line 1 "datastructure/sparsetable.cpp"

#include <bits/stdc++.h>
using namespace std;
#endif
//BEGIN CUT HERE
template<typename T>
struct SparseTable{
  using F = function<T(T, T)>;
  vector< vector<T> > dat;
  vector<int> ht;
  const F f;

  SparseTable(F f):f(f){}

  void build(const vector<T> &v){
    int n=v.size(),h=1;
    while((1<<h)<=n) h++;
    dat.assign(h,vector<T>(n));
    ht.assign(n+1,0);
    for(int j=2;j<=n;j++) ht[j]=ht[j>>1]+1;

    for(int j=0;j<n;j++) dat[0][j]=v[j];
    for(int i=1,p=1;i<h;i++,p<<=1)
      for(int j=0;j<n;j++)
        dat[i][j]=f(dat[i-1][j],dat[i-1][min(j+p,n-1)]);
  };

  T query(int a,int b){
    int l=b-a;
    return f(dat[ht[l]][a],dat[ht[l]][b-(1<<ht[l])]);
  }
};
//END CUT HERE
#ifndef call_from_test
signed main(){
  return 0;
}
#endif

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