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📜  检查给定数字在其二进制表示形式中是否仅包含“ 01”和“ 10”作为子字符串

📅  最后修改于: 2021-05-25 07:06:16             🧑  作者: Mango

给定数字N ,任务是检查数字N的二进制表示形式是否只有“ 01”“ 10”作为子字符串。如果发现是真的,则打印“是” 。否则,打印“否”
例子:

方法:可以使用以下观察结果解决给定的问题:

  • 由于subtring必须包含“ 01”“ 10” 。因此,二进制表示形式交替包含10
  • 对于交替包含01的二进制表示形式,可以观察到以下模式:
  • 上面的模式是2 * x(4 * x +1)的形式,使得该系列的最后一项是x

根据以上观察,想法是使用上述模式生成给定的序列,并检查该模式中是否存在给定的数字。如果发现是真的,则打印“是” 。否则,打印“否”
下面是上述方法的实现:

C++
// C++ program for the above approach
 
#include "bits/stdc++.h"
using namespace std;
 
vector Ans;
 
// Function to generate all numbers
// having "01" and "10" as a substring
void populateNumber()
{
    // Insert 2 and 5
    Ans.push_back(2);
    Ans.push_back(5);
 
    long long int x = 5;
 
    // Iterate till x is 10 ^ 15
    while (x < 1000000000001) {
 
        // Multiply x by 2
        x *= 2;
        Ans.push_back(x);
 
        // Update x as x*2  + 1
        x = x * 2 + 1;
 
        Ans.push_back(x);
    }
}
 
// Function to check if binary representation
// of N contains only "01" and "10" as substring
string checkString(long long int N)
{
    // Function Call to generate all
    // such numbers
    populateNumber();
 
    // Check if a number N
    // exists in Ans[] or not
    for (auto& it : Ans) {
 
        // If the number exists
        if (it == N) {
            return "Yes";
        }
    }
 
    // Otherwise
    return "No";
}
 
// Driver Code
int main()
{
    long long int N = 5;
 
    // Function Call
    cout << checkString(N);
 
    return 0;
}


Java
// Java Program to implement
// the above approach
import java.util.*;
class GFG
{
  static int N = 200000;
 
  static long Ans[] = new long [200000];
  static int index = 0;
 
  // Function to generate all numbers
  // having "01" and "10" as a substring
  static void populateNumber()
  {
    // Insert 2 and 5
    Ans[index++] = (2);
    Ans[index++] = (5);
    long x = 5;
    long inf = 1000000000001L;
 
    // Iterate till x is 10 ^ 15
    while (x < inf)
    {
 
      // Multiply x by 2
      x *= 2;
      Ans[index++] = (x);
 
      // Update x as x*2  + 1
      x = x * 2 + 1;
 
      Ans[index++] = (x);
    }
  }
  // Function to check if binary representation
  // of N contains only "01" and "10" as substring
  static void checkString(int N)
  {
    // Function Call to generate all
    // such numbers
    populateNumber();
 
    // Check if a number N
    // exists in Ans[] or not
    for (int i = 0; i < index; i++)
    {
 
      // If the number exists
      if (Ans[i] == N)
      {
        System.out.println("YES");
        return;
      }
    }
    System.out.println("NO");
 
  }
 
 
  // Driver Code
  public static void main(String[] args)
  {
    N = 5;
    checkString(N);
  }
}
 
// This code is contributed by amreshkumar3.


Python3
# Python3 program to implement
# the above approach
Ans = []
 
# Function to generate all numbers
# having "01" and "10" as a substring
def populateNumber() :
     
    # Insert 2 and 5
    Ans.append(2)
    Ans.append(5)
    x = 5
 
    # Iterate till x is 10 ^ 15
    while (x < 1000000000001) :
 
        # Multiply x by 2
        x *= 2
        Ans.append(x)
 
        # Update x as x*2  + 1
        x = x * 2 + 1
        Ans.append(x)
 
# Function to check if binary representation
# of N contains only "01" and "10" as substring
def checkString(N) :
     
    # Function Call to generate all
    # such numbers
    populateNumber()
 
    # Check if a number N
    # exists in Ans[] or not
    for it in Ans :
 
        # If the number exists
        if (it == N) :
            return "Yes"
 
    # Otherwise
    return "No"
 
# Driver Code
N = 5
 
# Function Call
print(checkString(N))
 
# This code is contributed by sanjoy_62


C#
// C# Program to implement
// the above approach
using System;
class GFG
{
  static int N = 200000;
  static long []Ans = new long [200000];
  static int index = 0;
 
  // Function to generate all numbers
  // having "01" and "10" as a substring
  static void populateNumber()
  {
     
    // Insert 2 and 5
    Ans[index++] = (2);
    Ans[index++] = (5);
    long x = 5;
    long inf = 1000000000001L;
 
    // Iterate till x is 10 ^ 15
    while (x < inf)
    {
 
      // Multiply x by 2
      x *= 2;
      Ans[index++] = (x);
 
      // Update x as x*2  + 1
      x = x * 2 + 1;
      Ans[index++] = (x);
    }
  }
   
  // Function to check if binary representation
  // of N contains only "01" and "10" as substring
  static void checkString(int N)
  {
     
    // Function Call to generate all
    // such numbers
    populateNumber();
 
    // Check if a number N
    // exists in Ans[] or not
    for (int i = 0; i < index; i++)
    {
 
      // If the number exists
      if (Ans[i] == N)
      {
        Console.WriteLine("YES");
        return;
      }
    }
    Console.WriteLine("NO");
  }
 
  // Driver Code
  public static void Main(String[] args)
  {
    N = 5;
    checkString(N);
  }
}
 
// This code is contributed by shikhasingrajput


Javascript


输出:
Yes

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