打印数字 N 的按位“与”集
原文:https://www . geesforgeks . org/print-bitwise-and-set-of-a-number-n/
给定一个数字 N，打印所有的数字，这些数字是 N 的二进制表示的按位“与”集合。按位“与”集合 N 是所有可能的小于或等于 N 的数字 x，使得对于某个数字 I，N & i 等于 x
示例:
Input : N = 5
Output : 0, 1, 4, 5
Explanation: 0 & 5 = 0
1 & 5 = 1
2 & 5 = 0
3 & 5 = 1
4 & 5 = 4
5 & 5 = 5
So we get 0, 1, 4 and 5 in the
bitwise subsets of N.
Input : N = 9
Output : 0, 1, 8, 9
简单方法:一个天真的方法是从 0 到 N 迭代所有的数字，检查是否(N & i == i)。打印满足指定条件的数字。
以下是上述想法的实现:
C++
// CPP program to print all bitwise
// subsets of N (Naive approach)
#include <bits/stdc++.h>
using namespace std;
// function to find bitwise subsets
// Naive approach
void printSubsets(int n) {
for (int i = 0; i <= n; i++)
if ((n & i) == i)
cout << i << " ";
}
// Driver Code
int main() {
int n = 9;
printSubsets(n);
return 0;
}
Java 语言(一种计算机语言，尤用于创建网站)
// JAVA program to print all bitwise
// subsets of N (Naive approach)
class GFG {
// function to find bitwise subsets
// Naive approach
static void printSubsets(int n)
{
for (int i = 0; i <= n; i++)
if ((n & i) == i)
System.out.print(i + " ");
}
// Driver function
public static void main(String[] args)
{
int n = 9;
printSubsets(n);
}
}
// This code is contributed by Anant Agarwal.
Python 3
# Python program to print all bitwise
# subsets of N (Naive approach)
def printSubsets(n):
for i in range(n + 1):
if ((n & i) == i):
print(i ," ", end = "")
# Driver code
n = 9
printSubsets(n)
# This code is contributed by Anant Agarwal.
C
// C# program to print all bitwise
// subsets of N (Naive approach)
using System;
class GFG {
// function to find bitwise subsets
// Naive approach
static void printSubsets(int n)
{
for (int i = 0; i <= n; i++)
if ((n & i) == i)
Console.Write(i + " ");
}
// Driver function
public static void Main()
{
int n = 9;
printSubsets(n);
}
}
// This code is contributed by vt_m.
服务器端编程语言（Professional Hypertext Preprocessor 的缩写）
<?php
// PHP program to print all bitwise
// subsets of N (Naive approach)
// function to find bitwise subsets
// Naive approach
function printSubsets($n)
{
for ($i = 0; $i <= $n; $i++)
if (($n & $i) == $i)
echo $i." ";
}
// Driver Code
$n = 9;
printSubsets($n);
// This code is contributed by mits
?>
java 描述语言
<script>
// JavaScript program to print all bitwise
// subsets of N (Efficient approach)
// function to find bitwise
// subsets Efficient approach
function printSubsets(n)
{
for (let i = n; i > 0; i = (i - 1) & n)
document.write(i + " ");
document.write(" 0 ");
}
// Driver code
let n = 9;
printSubsets(n);
// This code is contributed by souravghosh0416.
</script>
输出:
0 1 8 9
时间复杂度: O(N)
高效解决方案:高效的解决方案是使用按位运算符来查找子集。我们可以只迭代按位子集，而不是迭代每个 I。向后迭代 i=(i-1) & n 给我们每个按位子集，其中我从 n 开始，以 1 结束。
以下是上述想法的实现:
C++
// CPP program to print all bitwise
// subsets of N (Efficient approach)
#include <bits/stdc++.h>
using namespace std;
// function to find bitwise subsets
// Efficient approach
void printSubsets(int n) {
for (int i = n; i > 0; i = (i - 1) & n)
cout << i << " ";
cout << 0;
}
// Driver Code
int main() {
int n = 9;
printSubsets(n);
return 0;
}
Java 语言(一种计算机语言，尤用于创建网站)
// Java program to print all bitwise
// subsets of N (Efficient approach)
class GFG
{
// function to find bitwise
// subsets Efficient approach
static void printSubsets(int n)
{
for (int i = n; i > 0; i = (i - 1) & n)
System.out.print(i + " ");
System.out.print(" 0 ");
}
// Driver Code
public static void main(String[] args)
{
int n = 9;
printSubsets(n);
}
}
// This code is contributed by ajit.
Python 3
# Python 3 program to
# print all bitwise
# subsets of N
# (Efficient approach)
# function to find
# bitwise subsets
# Efficient approach
def printSubsets(n):
i=n
while(i != 0):
print(i,end=" ")
i=(i - 1) & n
print("0")
# Driver Code
n = 9
printSubsets(n)
# This code is contributed by
# Smith Dinesh Semwal
C
// C# program to print all bitwise
// subsets of N (Efficient approach)
using System;
public class GFG {
// function to find bitwise subsets
// Efficient approach
static void printSubsets(int n) {
for (int i = n; i > 0; i = (i - 1) & n)
Console.Write(i +" ");
Console.WriteLine("0");
}
// Driver Code
static public void Main () {
int n = 9;
printSubsets(n);
}
}
// This code is contributed by vt_m.
服务器端编程语言（Professional Hypertext Preprocessor 的缩写）
<?php
// PHP program to print all bitwise
// subsets of N (Efficient approach)
// function to find bitwise subsets
// Efficient approach
function printSubsets($n)
{
for ($i = $n; $i > 0;
$i = ($i - 1) & $n)
echo $i." ";
echo "0";
}
// Driver Code
$n = 9;
printSubsets($n);
// This code is contributed by mits
?>
java 描述语言
<script>
// Javascript program to print all bitwise
// subsets of N (Efficient approach)
// Function to find bitwise subsets
// Efficient approach
function printSubsets(n)
{
for(let i = n; i > 0; i = (i - 1) & n)
document.write(i +" ");
document.write("0" + "</br>");
}
// Driver code
let n = 9;
printSubsets(n);
// This code is contributed by divyesh072019
</script>
输出:
9 8 1 0
时间复杂度 : O(K)，其中 K 是 n 的按位子集数
版权属于：月萌API www.moonapi.com，转载请注明出处
