# Set bits in N equals to M in the given range.

You are given two 32-bit numbers, N and M, and two bit positions, i and j. Write a method to set all bits between i and j in N equal to M (e.g., M becomes a substring of N located at i and starting at j).**Examples :**

Input : N = 1, M = 2, i = 2, j = 4 Output: 9 N = 00000001(Considering 8 bits only) M = 10 (Binary of 2) For more indexes, leading zeroes will be considered. Now set 3 bits from ith index to j in the N as in the M. Bits:- 0 0 0 (0 1 0) 0 1 = 9 Indexes:- 7 6 5 4 3 2 1 0 From index 2 to 4, bits are set according to the M.

Asked in : Adobe

A simple solution is to traverse all bits in N from 0 to 31 and set the bits equals to M in the range from i to j.

An efficient solution is to do following steps.

- Set all the bits after j in a number.
- Set all the bits before i in a number.
- Then perform Bitwise Or on both then we get the number with all the bits set except from i to j.
- Perform Bitwise And with the given N as to set the bits according to the N.
- Then shift M into the correct position i.e. in the range of i to j.
- And at the last perform Bitwise Or on (Shifted M and the N modified in 4th step).
- The result will be N with M as substring from ith to jth bits

## C++

`// C++ program for above implementation` `#include <iostream>` `using` `namespace` `std;` `// Function to set the bits` `int` `setBits(` `int` `n, ` `int` `m, ` `int` `i, ` `int` `j)` `{` ` ` `// number with all 1's` ` ` `int` `allOnes = ~0;` ` ` `// Set all the bits in the left of j` ` ` `int` `left = allOnes << (j + 1);` ` ` `// Set all the bits in the right of j` ` ` `int` `right = ((1 << i) - 1);` ` ` `// Do Bitwsie OR to get all the bits` ` ` `// set except in the range from i to j` ` ` `int` `mask = left | right;` ` ` `// clear bits j through i` ` ` `int` `masked_n = n & mask;` ` ` `// move m into the correct position` ` ` `int` `m_shifted = m << i;` ` ` `// return the Bitwise OR of masked_n` ` ` `// and shifted_m` ` ` `return` `(masked_n | m_shifted);` `}` `// Drivers program` `int` `main()` `{` ` ` `int` `n = 2, m = 4;` ` ` `int` `i = 2, j = 4;` ` ` `cout << setBits(n, m, i, j);` ` ` `return` `0;` `}` |

## Java

`// Java Program` `public` `class` `GFG` `{` ` ` `// Function to set the bits` ` ` `static` `int` `setBits(` `int` `n, ` `int` `m, ` `int` `i, ` `int` `j)` ` ` `{` ` ` ` ` `// number with all 1's` ` ` `int` `allOnes = ~` `0` `;` ` ` ` ` `// Set all the bits in the left of j` ` ` `int` `left = allOnes << (j + ` `1` `);` ` ` ` ` `// Set all the bits in the right of j` ` ` `int` `right = ((` `1` `<< i) - ` `1` `);` ` ` ` ` `// Do Bitwise OR to get all the bits` ` ` `// set except in the range from i to j` ` ` `int` `mask = left | right;` ` ` ` ` `// clear bits j through i` ` ` `int` `masked_n = n & mask;` ` ` ` ` `// move m into the correct position` ` ` `int` `m_shifted = m << i;` ` ` ` ` `// return the Bitwise OR of masked_n` ` ` `// and shifted_m` ` ` `return` `(masked_n | m_shifted);` ` ` `}` ` ` ` ` `// Driver Program to test above function` ` ` `public` `static` `void` `main(String[] args)` ` ` `{` ` ` `int` `n = ` `2` `, m = ` `4` `;` ` ` `int` `i = ` `2` `, j = ` `4` `;` ` ` `System.out.println(setBits(n, m, i, j));` ` ` `}` `}` `// This code is contributed by Sumit Ghosh` |

## Python

`# Python program for above implementation` `# Function to set the bits` `def` `setBits(n, m, i, j):` ` ` `# number with all 1's` ` ` `allOnes ` `=` `not` `0` ` ` ` ` `# Set all the bits in the left of j` ` ` `left ` `=` `allOnes << (j ` `+` `1` `)` ` ` ` ` `# Set all the bits in the right of j` ` ` `right ` `=` `((` `1` `<< i) ` `-` `1` `)` ` ` ` ` `# Do Bitwsie OR to get all the bits` ` ` `# set except in the range from i to j` ` ` `mask ` `=` `left | right` ` ` ` ` `# clear bits j through i` ` ` `masked_n ` `=` `n & mask` ` ` ` ` `# move m into the correct position` ` ` `m_shifted ` `=` `m << i` ` ` ` ` `# return the Bitwise OR of masked_n` ` ` `# and shifted_m` ` ` `return` `(masked_n | m_shifted)` ` ` `# Drivers program` `n, m ` `=` `2` `, ` `4` `i, j ` `=` `2` `, ` `4` `print` `setBits(n, m, i, j)` `# This code is submitted by Sachin Bisht` |

## C#

`// C# Program for above implementation` `using` `System;` `public` `class` `GFG {` ` ` ` ` `// Function to set the bits` ` ` `static` `int` `setBits(` `int` `n, ` `int` `m, ` `int` `i, ` `int` `j)` ` ` `{` ` ` ` ` `// number with all 1's` ` ` `int` `allOnes = ~0;` ` ` ` ` `// Set all the bits in the left of j` ` ` `int` `left = allOnes << (j + 1);` ` ` ` ` `// Set all the bits in the right of j` ` ` `int` `right = ((1 << i) - 1);` ` ` ` ` `// Do Bitwise OR to get all the bits` ` ` `// set except in the range from i to j` ` ` `int` `mask = left | right;` ` ` ` ` `// clear bits j through i` ` ` `int` `masked_n = n & mask;` ` ` ` ` `// move m into the correct position` ` ` `int` `m_shifted = m << i;` ` ` ` ` `// return the Bitwise OR of masked_n` ` ` `// and shifted_m` ` ` `return` `(masked_n | m_shifted);` ` ` `}` ` ` ` ` `// Driver Program to test above function` ` ` `public` `static` `void` `Main()` ` ` `{` ` ` `int` `n = 2, m = 4;` ` ` `int` `i = 2, j = 4;` ` ` ` ` `Console.WriteLine(setBits(n, m, i, j));` ` ` `}` `}` `// This code is contributed by Anant Agarwal.` |

## PHP

`<?php` `// PHP program for above implementation` `// Function to set the bits` `function` `setBits(` `$n` `, ` `$m` `, ` `$i` `, ` `$j` `)` `{` ` ` `// number with all 1's` ` ` `$allOnes` `= ~0;` ` ` `// Set all the bits` ` ` `// in the left of j` ` ` `$left` `= ` `$allOnes` `<< (` `$j` `+ 1);` ` ` `// Set all the bits` ` ` `// in the right of j` ` ` `$right` `= ((1 << ` `$i` `) - 1);` ` ` `// Do Bitwsie OR to get all` ` ` `// the bits set except in` ` ` `// the range from i to j` ` ` `$mask` `= ` `$left` `| ` `$right` `;` ` ` `// clear bits j through i` ` ` `$masked_n` `= ` `$n` `& ` `$mask` `;` ` ` `// move m into the` ` ` `// correct position` ` ` `$m_shifted` `= ` `$m` `<< ` `$i` `;` ` ` `// return the Bitwise OR` ` ` `// of masked_n and shifted_m` ` ` `return` `(` `$masked_n` `| ` `$m_shifted` `);` `}` `// Driver Code` `$n` `= 2; ` `$m` `= 4;` `$i` `= 2; ` `$j` `= 4;` `echo` `setBits(` `$n` `, ` `$m` `, ` `$i` `, ` `$j` `);` `// This code is contributed by ajit` `?>` |

## Javascript

`<script>` ` ` `// Javascript Program for above implementation` ` ` ` ` `// Function to set the bits` ` ` `function` `setBits(n, m, i, j)` ` ` `{` ` ` ` ` `// number with all 1's` ` ` `let allOnes = ~0;` ` ` ` ` `// Set all the bits in the left of j` ` ` `let left = allOnes << (j + 1);` ` ` ` ` `// Set all the bits in the right of j` ` ` `let right = ((1 << i) - 1);` ` ` ` ` `// Do Bitwise OR to get all the bits` ` ` `// set except in the range from i to j` ` ` `let mask = left | right;` ` ` ` ` `// clear bits j through i` ` ` `let masked_n = n & mask;` ` ` ` ` `// move m into the correct position` ` ` `let m_shifted = m << i;` ` ` ` ` `// return the Bitwise OR of masked_n` ` ` `// and shifted_m` ` ` `return` `(masked_n | m_shifted);` ` ` `}` ` ` ` ` `let n = 2, m = 4;` ` ` `let i = 2, j = 4;` ` ` `document.write(setBits(n, m, i, j));` ` ` `</script>` |

**Output :**

18

Reference:

https://www.careercup.com/question?id=8863294

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