Dada una string binaria, la tarea es convertir esta string en complemento a dos con la ayuda del operador XOR.
Ejemplos:
Input : 00000101 Output :11111011 Input : 10010 Output : 01110
Hemos discutido un enfoque en una publicación anterior para encontrar el complemento de 2
Para el complemento a 2, primero encontramos el complemento a uno. Recorremos el complemento a uno comenzando desde LSB (bit menos significativo) y buscamos el 0. Volteamos todos los 1 (cambiamos a 0) hasta encontrar un 0. Finalmente, volteamos el 0 encontrado.
Atravesamos desde el último bot y seguimos ignorando todos los 0 hasta que encontramos un 1. También ignoramos el primer 1. Luego alternamos todos los bits haciendo XOR con 1.
C++
// C++ program to find 2's complement using XOR.
#include <bits/stdc++.h>
using namespace std;
string TwoscomplementbyXOR(string str)
{
int n = str.length();
// A flag used to find if a 1 bit is seen
// or not.
bool check_bit = 0;
for (int i = n - 1; i >= 0; i--) {
if (str[i] == '0' && check_bit == 0) {
continue;
}
else {
// xor operator is used to flip the
if (check_bit == 1)
str[i] = (str[i] - '0') ^ 1 + '0';
// bits after converting in to
// ASCII values
check_bit = 1;
}
}
// if there is no 1 in the string so just add
// 1 in starting of string and return
if (check_bit == 0)
return "1" + str;
else
return str;
}
// Driver code
int main()
{
string str = "101";
cout << TwoscomplementbyXOR(str);
return 0;
}
Java
// Java program to find 2's complement using XOR.
import java.util.*;
class GFG{
static void TwoscomplementbyXOR(String str)
{
int n = str.length();
// A flag used to find if a 1 bit is seen
// or not.
boolean check_bit = false;
for(int i = n - 1; i >= 0; i--)
{
if (str.charAt(i) == '0' &&
check_bit == false)
{
continue;
}
else
{
// xor operator is used to flip the
if (check_bit == true)
{
if (str.charAt(i) == '0')
str = str.substring(0, i) + '1' +
str.substring(i + 1);
else
str = str.substring(0, i) + '0' +
str.substring(i + 1);
}
// bits after converting in to
// ASCII values
check_bit = true;
}
}
// If there is no 1 in the string so just add
// 1 in starting of string and return
if (check_bit == false)
{
System.out.println("1" + str);
}
else
System.out.println(str);
}
// Driver code
public static void main(String[] args)
{
String str = "101";
TwoscomplementbyXOR(str);
}
}
// This code is contributed by amreshkumar3
Python3
# Python program to find 2's complement using XOR. def TwoscomplementbyXOR(str): n = len(str) # A flag used to find if a 1 bit is seen # or not. check_bit = 0 i = n - 1 s = list(str) while (i >= 0): if (s[i] == '0' and check_bit == 0): continue else: # xor operator is used to flip the if (check_bit == 1): s[i] = chr((ord(s[i]) - 48) ^ 1 + 48) # bits after converting in to # ASCII values check_bit = 1 i -= 1 # if there is no 1 in the string so just add # 1 in starting of string and return str = "".join(s) if (check_bit == 0): return "1" + str else: return str # Driver code str = "101" print(TwoscomplementbyXOR(str)) # This code is contributed by subhammahato348.
C#
// C# program to find 2's complement using XOR.
using System;
class GFG {
static void TwoscomplementbyXOR(string str)
{
int n = str.Length;
// A flag used to find if a 1 bit is seen
// or not.
bool check_bit = false;
for(int i = n - 1; i >= 0; i--)
{
if (str[i] == '0' &&
check_bit == false)
{
continue;
}
else
{
// xor operator is used to flip the
if (check_bit == true)
{
if (str[i] == '0')
str = str.Substring(0, i) + '1' +
str.Substring(i + 1);
else
str = str.Substring(0, i) + '0' +
str.Substring(i + 1);
}
// bits after converting in to
// ASCII values
check_bit = true;
}
}
// If there is no 1 in the string so just add
// 1 in starting of string and return
if (check_bit == false)
{
Console.WriteLine("1" + str);
}
else
Console.WriteLine(str);
}
// Driver code
static void Main() {
string str = "101";
TwoscomplementbyXOR(str);
}
}
// This code is contributed by divyeshrabadiya07.
PHP
<?php
// PHP program to find 2's complement
// using XOR.
function TwoscomplementbyXOR($str)
{
$n =strlen($str);
// A flag used to find if a 1
// bit is seen or not.
$check_bit = 0;
for ($i = $n - 1; $i >= 0; $i--)
{
if ($str[$i] == '0' &&
$check_bit == 0)
{
continue;
}
else
{
// xor operator is used
// to flip the
if ($check_bit == 1)
$str[$i] = ($str[$i] - '0') ^ 1 + '0';
// bits after converting in to
// ASCII values
$check_bit = 1;
}
}
// if there is no 1 in the string
// so just add 1 in starting of
// string and return
if ($check_bit == 0)
return "1" + $str;
else
return $str;
}
// Driver code
$str = "101";
echo TwoscomplementbyXOR($str);
// This code is contributed by akt_mit
?>
Javascript
<script>
// Javascript program to find 2's complement
// using XOR.
function TwoscomplementbyXOR(str) {
let n = str.length;
// A flag used to find if a 1
// bit is seen or not.
let check_bit = 0;
for (let i = n - 1; i >= 0; i--) {
if (str[i] == '0' && check_bit == 0) {
continue;
}
else {
// xor operator is used
// to flip the
if (check_bit == 1) {
if (str.charAt(i) == '0')
str = str.substr(0, i) + '1' + str.substr(i + 1);
else
str = str.substr(0, i) + '0' + str.substr(i + 1);
}
// bits after converting in to
// ASCII values
check_bit = 1;
}
}
// if there is no 1 in the string
// so just add 1 in starting of
// string and return
if (check_bit == 0)
return "1" + str;
else
return str;
}
// Driver code
let str = "101";
document.write(TwoscomplementbyXOR(str));
// This code is contributed by _saurabh_jaiswal
</script>
Producción:
011
Publicación traducida automáticamente
Artículo escrito por mubashshir ahmad y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA