Problem:
Score : 200 points

Problem Statement

Takahashi loves numbers divisible by 2.

You are given a positive integer N. Among the integers between 1 and N (inclusive), find the one that can be divisible by 2 for the most number of times. The solution is always unique.

Here, the number of times an integer can be divisible by 2, is how many times the integer can be divided by 2 without remainder.

For example,

6 can be divided by 2 once: 6 -> 3.

8 can be divided by 2 three times: 8 -> 4 -> 2 -> 1.

3 can be divided by 2 zero times.

Constraints

1 ≤ N ≤ 100

Input

Input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

7

Sample Output 1

4

4 can be divided by 2 twice, which is the most number of times among 1, 2, ..., 7.

Sample Input 2

32

Sample Output 2

32

Sample Input 3

1

Sample Output 3

1

Sample Input 4

100

Sample Output 4

64

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

//繰り返し二乗法 repow(b,p)(b,p,modder)
//ユークリッド互除法で最大公約数 gcd
//gcdで最小公倍数 lcm
//約数列挙divList(int)
//BSA()()()(List<T>,T,int,int,Comparator<T>)
//BSF()()()(List<T>,T,int,int,Comparator<T>)
//BSL()()()(List<T>,T,int,int,Comparator<T>)
//文字列文字ソートStSort(String)
//二次元整数座標オブジェクトXy
////マンハッタン距離manht(Xy)
////toString
////偏角ソート用hencom
////偏角henkaku
////equals
//スキャナーScnr
////next nextBuilder nextInt nextLong nextDouble()
////nextAint nextAlong nextAdouble(n)(a[],n)
//static PrintWriter out = new PrintWriter(System.out);
import java.util.*;
import java.io.*;

class Main{
  static int repow(int b,int p){
    long a = b;
    long res=1;
    while(p>0){
      if(p%2==1){
        res*=a;
      }
      a*=a;
      p/=2;
    }
    return (int)res;
  }
  static int repow(int b,int p,int modder){
    long a = b%modder;
    long res=1;
    while(p>0){
      if(p%2==1){
        res=(res*a)%modder;
      }
      a=(a*a)%modder;
      p/=2;
    }
    return (int)res;
  }
  static <T extends Number> long gcd(T cc,T dd){
    long c=cc.longValue();
    long d=dd.longValue();
    while(true){
      long f=c%d;
      if(f==0){
        return d;
      }
      c=d;
      d=f;   
    }
  }
  static <T extends Number> long lcm(T cc,T dd){
    long c=cc.longValue();
    long d=dd.longValue();
    return c/gcd(c,d)*d;
  }
  static ArrayList<Integer> divList(int n){
    ArrayList<Integer> div=new ArrayList<Integer>();
    for(int i=1;i*i<=n;i++){
      if(n%i==0){
        div.add(i);
        div.add((int)(n/i));
      }
    }
    return div;
  }
  static <T extends Comparable> int BSA(List<T> l,T target){
    return BSA(l,target,0,l.size(),(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSA(List<T> l,T target,Comparator<T> c){
    return BSA(l,target,0,l.size(),c);
  }
  static <T extends Comparable> int BSA(List<T> l,T target,int left,int right){
    return BSA(l,target,left,right,(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSA(List<T> l,T target,int left,int right,Comparator<T> c){
    int lt = left;
    int rt = right-1;
    while(lt<=rt){
      T gaze=l.get(lt+(rt-lt)/2);
      if(c.compare(gaze,target)<0){
        lt=lt+(rt-lt)/2+1;
      }else if(c.compare(gaze,target)>0){
        rt=lt+(rt-lt)/2-1;
      }else{
        return lt+(rt-lt)/2;
      }
    }
    return -1;
  }
  static <T extends Comparable> int BSF(List<T> l,T target){
    return BSF(l,target,0,l.size(),(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSF(List<T> l,T target,Comparator<T> c){
    return BSF(l,target,0,l.size(),c);
  }
  static <T extends Comparable> int BSF(List<T> l,T target,int left,int right){
    return BSF(l,target,left,right,(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSF(List<T> l,T target,int left,int right,Comparator<T> c){
    int lt = left;
    int rt = right-1;
    while(lt<=rt){
      T gaze=l.get(lt+(rt-lt)/2);
      if(c.compare(gaze,target)<0){
        lt=lt+(rt-lt)/2+1;
      }else if(c.compare(gaze,target)>=0){
        rt=lt+(rt-lt)/2-1;
      }
    }
    return lt;
  }
  static <T extends Comparable> int BSL(List<T> l,T target){
    return BSL(l,target,0,l.size(),(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSL(List<T> l,T target,Comparator<T> c){
    return BSL(l,target,0,l.size(),c);
  }
  static <T extends Comparable> int BSL(List<T> l,T target,int left,int right){
    return BSL(l,target,left,right,(s1,s2)->s1.compareTo(s2));
  }
  static <T> int BSL(List<T> l,T target,int left,int right,Comparator<T> c){
    int lt = left;
    int rt = right-1;
    while(lt<=rt){
      T gaze=l.get(lt+(rt-lt)/2);
      if(c.compare(gaze,target)<=0){
        lt=lt+(rt-lt)/2+1;
      }else if(c.compare(gaze,target)>0){
        rt=lt+(rt-lt)/2-1;
      }
    }
    return lt;
  }
  static String StSort(String s){
    StringBuilder sb = new StringBuilder(s);
    int lg = sb.length();
    int l;
    int r;
    int gaze;
    for(int i=1;i<lg;i++){
      l=0;
      r=i-1;
      while(l<=r){
        gaze=(l+r)/2;
        if(sb.charAt(gaze)<=sb.charAt(i)){
          l=gaze+1;
        }else if(sb.charAt(gaze)>sb.charAt(i)){
          r=gaze-1;
        }
      }
      sb.insert(l,sb.charAt(i));
      sb.deleteCharAt(i+1);
    }
    return sb.toString();
  }
  static class Xy{
    int x;
    int y;
    Xy(int x,int y){
      this.x=x;
      this.y=y;
    }
    public int manht(Xy o){
      return Math.abs(x-o.x)+Math.abs(y-o.y);
    }
    public String toString(){
      return "["+x+","+y+"]";
    }
    public double henkaku(){
      return Math.atan2(y,x);
    }
    public static int hencom(Xy s1,Xy s2){
      return (int)Math.signum(s1.henkaku()-s2.henkaku());
    }
    public boolean equals(Object o){
      return x==((Xy)o).x&&y==((Xy)o).y;
    }
  }
  static class Scnr{
    private final InputStream ins;
    private final byte[] buffer = new byte[1024];
    private int ptr = 0;
    private int buflen = 0;
    Scnr(){
      this(System.in);
    }
    Scnr(InputStream in){
      ins = in;
    }
    private boolean hasNextByte(){
      if(ptr<buflen){
        return true;
      }else{
        ptr = 0;
        try{
          buflen = ins.read(buffer);
        }catch(IOException e){
          e.printStackTrace();
        }
        if(buflen<=0){
          return false;
        }
      }
      return true;
    }
    private int readByte(){
      if(hasNextByte()){
        return buffer[ptr++];
      }else{
        return -1;
      }
    }
    private static boolean isPrintableChar(int c){
      return 33<=c&&c<=126;
    }
    public boolean hasNext(){
      while(hasNextByte()&&!isPrintableChar(buffer[ptr])){
        ptr++;
      }
      return hasNextByte();
    }
    public String next(){
      if(!hasNext()){
        throw new NoSuchElementException();
      }
      StringBuilder sb = new StringBuilder();
      int b = readByte();
      while(isPrintableChar(b)){
        sb.appendCodePoint(b);
        b = readByte();
      }
      return sb.toString();
    }
    public StringBuilder nextBuilder(){
      if(!hasNext()){
        throw new NoSuchElementException();
      }
      StringBuilder sb = new StringBuilder();
      int b = readByte();
      while(isPrintableChar(b)){
        sb.appendCodePoint(b);
        b = readByte();
      }
      return sb;
    }
    public double nextDouble(){
      return Double.parseDouble(next());
    }
    public long nextLong(){
      if(!hasNext()){
        throw new NoSuchElementException();
      }
      long n = 0;
      boolean minus = false;
      int b = readByte();
      if(b=='-'){
        minus=true;
        b=readByte();
      }
      if(b<'0'||'9'<b){
        throw new NumberFormatException();
      }
      while(true){
        if('0'<=b&&b<='9'){
          n*=10;
          n+=b-'0';
        }else if(b==-1||!isPrintableChar(b)){
          return minus?-n:n;
        }else{
          throw new NumberFormatException();
        }
        b=readByte();
      }
    }
    public int nextInt(){
      long nl=nextLong();
      if(nl<Integer.MIN_VALUE||Integer.MAX_VALUE<nl){
        throw new NumberFormatException();
      }
      return (int) nl;
    }
    public int[] nextAInt(int n){
      int[] a = new int[n];
      nextAInt(a,n);
      return a;
    }
    public void nextAInt(int[] a,int n){
      for(int i=0;i<n;i++){
        a[i] = nextInt();
      }
    }
    public long[] nextALong(int n){
      long[] a = new long[n];
      nextALong(a,n);
      return a;
    }
    public void nextALong(long[] a,int n){
      for(int i=0;i<n;i++){
        a[i] = nextLong();
      }
    }
    public double[] nextADouble(int n){
      double[] a = new double[n];
      for(int i=0;i<n;i++){
        a[i] = nextDouble();
      }
      return a;
    }
    public void nextADouble(double[] a,int n){
      for(int i=0;i<n;i++){
        a[i] = nextDouble();
      }
    }
  }
  
  static Scnr sc = new Scnr();
  static PrintWriter out = new PrintWriter(System.out);
  public static void main(String args[]){
    int n=sc.nextInt();
    int i;
    for(i=1;i<=n;i*=2){}
    out.println(i/2);
    out.flush();
  }
}