使用递归从十进制到二进制数

给定一个十进制数作为输入，我们需要编写一个程序将给定的十进制数转换为等效的二进制数。

例子 ：

Input : 7                                                         
Output :111

Input :10
Output :1010

我们在下面的文章中讨论了一种迭代解决方案。
十进制转换为二进制的程序
以下是递归解决方案：

findBinary(decimal)
   if (decimal == 0)
      binary = 0
   else
      binary = decimal % 2 + 10 * (findBinary(decimal / 2)

分步执行的过程，可以更好地了解算法的工作原理
设十进制数为10。
步骤1-> 10％2等于-0 + 10 *(10/2)％2
步骤2-> 5％2等于1 + 10 *(5/2)％2
步骤3-> 2％2等于0 + 10 *(2/2)％2
步骤4-> 1％2等于1 + 10 *(1/2)％2

C++

// C++ program for decimal to binary
// conversion using recursion
#include 
using namespace std;
 
// Decimal to binary conversion
// using recursion
int find(int decimal_number)
{
    if (decimal_number == 0)
        return 0;
    else
        return (decimal_number % 2 + 10 *
                find(decimal_number / 2));
}
 
// Driver code
int main()
{
    int decimal_number = 10;
    cout << find(decimal_number);
    return 0;
}
// This code is contributed by shivanisinghss2110

C

// C/C++ program for decimal to binary
// conversion using recursion
#include 
 
// Decimal to binary conversion
// using recursion
int find(int decimal_number)
{
    if (decimal_number == 0)
        return 0;
    else
        return (decimal_number % 2 + 10 *
                find(decimal_number / 2));
}
 
// Driver code
int main()
{
    int decimal_number = 10;
    printf("%d", find(decimal_number));
    return 0;
}

Java

// Java program for decimal to binary
// conversion using recursion
import java.io.*;
 
class GFG
{
     
    // Decimal to binary conversion
    // using recursion
    static int find(int decimal_number)
    {
        if (decimal_number == 0)
            return 0;
             
        else
         
        return (decimal_number % 2 + 10 *
                find(decimal_number / 2));
    }
     
// Driver Code
public static void main(String args[])
{
    int decimal_number = 10;
    System.out.println(find(decimal_number));
}
 
}
 
// This code is contributed by Nikita Tiwari

Python3

# Python3 code for decimal to binary
# conversion using recursion
 
# Decimal to binary conversion
# using recursion
def find( decimal_number ):
    if decimal_number == 0:
        return 0
    else:
        return (decimal_number % 2 + 10 *
                find(int(decimal_number // 2)))
 
# Driver Code
decimal_number = 10
print(find(decimal_number))
 
# This code is contributed
# by "Sharad_Bhardwaj"

C#

// C# program for decimal to binary
// conversion using recursion
using System;
 
class GFG
{
     
    // Decimal to binary conversion
    // using recursion
    static int find(int decimal_number)
    {
        if (decimal_number == 0)
            return 0;
             
        else
         
        return (decimal_number % 2 + 10 *
                find(decimal_number / 2));
    }
     
    // Driver Code
    public static void Main()
    {
         
        int decimal_number = 10;
         
        Console.WriteLine(find(decimal_number));
    }
}
 
// This code is contributed by vt_m

---

输出

1010

除非您希望将大于1023的十进制数字转换为二进制，否则上述方法可以正常工作。 1024的二进制数是10000000000(1和10的0)，超出了int的范围。即使使用long long unsigned作为返回类型，您可以得到的最大值是1048575，这远小于int的范围。一种更简单但有效的方法是将二进制数的各个数字存储在bool向量中。

C++

// C++ program for decimal to binary
// conversion using recursion
#include
using namespace std;
 
 
// Function to convert decimal to binary
void deci_to_bin(int x, string & bin_num)
{
   
    // Base Case
    if (x <= 1)
        bin_num += (char)(x + '0');
    else {
       
        // Recursion call
        deci_to_bin(x / 2, bin_num);
       
        // If x is divisible by 2
        if(x%2)
          bin_num += '1';
       
        // otherwise
        else
          bin_num += '0';
    }
}
 
// Driver Code
int main()
{
    string bin_num = "";
    deci_to_bin(1048576, bin_num);
     
    cout<

Python3

# Python3 code for decimal to binary
# conversion using recursion
  
# Decimal to binary conversion
# using recursion
def getbinary(number):
   
    # Base case
    if number == 0:
        return 0
       
     # Recursion call and storing the result
    smallans = getbinary(number // 2)
     
    return number % 2 + 10 * smallans
   
# Driver Code
decimal_number = 1048576
print(getbinary(decimal_number))
  
# This code is contributed
# by "Sarthak Sethi"

输出

100000000000000000000