设置给定数字的第K位-yiteyi-C++库

给定一个数字n和一个值k。从右边开始，在n的二进制表示中设置第k位。LSB（或最后一位）的位置为0，最后一位的位置为1，依此类推。此外，0<=k 例如：

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Input : n = 10, k = 2Output : 14(10)₁₀ = (1010)₂Now, set the 2nd bit from right.(14)₁₀ = (1110)₂2nd bit has been set.Input : n = 15, k = 3Output : 153rd bit of 15 is already set.

建议：请在“上解决” 实践 “首先，在讨论解决方案之前。

要设置任何位，我们使用按位或|运算符。我们已经知道，如果操作数的任何对应位被设置（1），按位或|运算符将结果的每一位计算为1。为了设置一个数字的第k位，我们需要将其向左移位1k次，然后执行按位OR运算，并在之前执行左移位的数字和结果。

                            In general, (1 << k) | n.

C++

                         // C++ implementation to set the kth bit                       
                         // of the given number                       
                         #include <bits/stdc++.h>                       
           
                         using                                     namespace                                     std;                       
           
                         // function to set the kth bit                       
                         int                                     setKthBit(                                     int                                     n,                                     int                                     k)                       
                         {                       
                                                 // kth bit of n is being set by this operation                       
                                                 return                                     ((1 << k) | n);                       
                         }                       
           
                         // Driver program to test above                       
                         int                                     main()                       
                         {                       
                                                 int                                     n = 10, k = 2;                       
                                                 cout <<                                     "Kth bit set number = "                       
                                                 << setKthBit(n, k);                       
                                                 return                                     0;                       
                         }                       

JAVA

                         // Java implementation to set the kth bit                       
                         // of the given number                       
           
                         class                                     GFG {                       
                                   
                         // function to set the kth bit                       
                         static                                     int                                     setKthBit(                                     int                                     n,                                     int                                     k)                       
                         {                       
                                                 // kth bit of n is being set by this operation                       
                                                 return                                     ((                                     1                                     << k) | n);                       
                         }                       
           
                         // Driver code                       
                         public                                     static                                     void                                     main(String arg[])                       
                         {                       
                                                 int                                     n =                                     10                                     , k =                                     2                                     ;                       
                                                 System.out.print(                                     "Kth bit set number = "                                     +                       
                                                 setKthBit(n, k));                       
                         }                       
                         }                       
           
                         // This code is contributed by Anant Agarwal.                       

Python3

                         # Python implementation                       
                         # to set the kth bit                       
                         # of the given number                       
           
                         # function to set                       
                         # the kth bit                       
                         def                                     setKthBit(n,k):                       
           
                                                 # kth bit of n is being                       
                                                 # set by this operation                       
                                                 return                                     ((                                     1                                     << k) | n)                       
                                   
                         # Driver code                       
           
                         n                                     =                                     10                       
                         k                                     =                                     2                       
           
                         print                                     (                                     "Kth bit set number = "                                     ,                       
                                                 setKthBit(n, k))                       
           
                         # This code is contributed                       
                         # by Anant Agarwal.                       

C#

                         // C# implementation to set the                       
                         // kth bit of the given number                       
                         using                                     System;                       
           
                         class                                     GFG {                       
                                   
                         // function to set the kth bit                       
                         static                                     int                                     setKthBit(                                     int                                     n,                                     int                                     k)                       
                         {                       
                                                 // kth bit of n is being set                       
                                                 // by this operation                       
                                                 return                                     ((1 << k) | n);                       
                         }                       
           
                         // Driver code                       
                         public                                     static                                     void                                     Main()                       
                         {                       
                                                 int                                     n = 10, k = 2;                       
                                                 Console.Write(                                     "Kth bit set number = "                       
                                                 + setKthBit(n, k));                       
                                   
                         }                       
                         }                       
           
                         // This code is contributed by                       
                         // Smitha Dinesh Semwal.                       

PHP

                         <?php                       
                         // PHP implementation to                       
                         // set the kth bit of                       
                         // the given number                       
           
                         // function to set                       
                         // the kth bit                       
                         function                                     setKthBit(                                     $n                                     ,                                     $k                                     )                       
                         {                       
                                                 // kth bit of n is being                       
                                                 // set by this operation                       
                                                 return                                     ((1 <<                                     $k                                     ) |                                     $n                                     );                       
                         }                       
           
                         // Driver Code                       
                         $n                                     = 10;                                     $k                                     = 2;                       
                         echo                                     "Kth bit set number = "                                     ,                       
                                                 setKthBit(                                     $n                                     ,                                     $k                                     );                       
           
                         // This code is contributed by m_kit                       
                         ?>                       

Javascript

                         <script>                       
                                                 // Javascript implementation to set the                       
                                                 // kth bit of the given number                       
                                   
                                                 // function to set the kth bit                       
                                                 function                                     setKthBit(n, k)                       
                                                 {                       
                                                 // kth bit of n is being set                       
                                                 // by this operation                       
                                                 return                                     ((1 << k) | n);                       
                                                 }                       
                                   
                                                 let n = 10, k = 2;                       
                                                 document.write(                                     "Kth bit set number = "                                     + setKthBit(n, k));                       
                                   
                                                 // This code is contributed by rameshtravel07.                       
                         </script>                       

输出：

Kth bit set number = 14

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