Introdução à Troca em PHP
Neste artigo, aprenderemos a troca de números em PHP. Aprenderemos como definimos a troca, aprenderemos a codificar para trocar dois números, como trocar mais de dois e três números e como trocar números com ou sem variáveis temporárias e muito mais.
Vamos começar com a definição primeiro.
"Trocar em PHP é um termo definido como troca de valores."
A troca de dois números é um processo para trocar dois valores usando ou sem o uso de uma variável temporária. Espero que esses exemplos sejam úteis para todos os programadores que desejam aprender o conceito de troca.
Como trocar dois números em PHP?
Existem duas maneiras de trocar números. Esses números mantêm valores numéricos.
- Trocando dois números por uma variável temporária.
- Trocando dois números sem uma variável temporária.
Suponha que tenhamos uma variável com um valor 10,
número1 = 10;
E a outra variável com um valor 20,
número2 = 20;
Na troca desses dois números, o resultado deve ser,
number1 = 20
number2 = 10
Isso é possível com o uso da terceira variável temporária e também sem uma variável temporária. A troca de dois números pode ser feita usando os operadores +, -, *, /.
1. Trocando dois números por uma variável temporária
Código:
// Example of swapping of two numbers using a temporary variable <_?php
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Before Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo “ ”;
// declaring temporary variable to be zero
$temp = 0;
// performing swap of numbers
$temp = $num1;
$num1 = $num2;
$num2 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Before Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo “ ”;
// declaring temporary variable to be zero
$temp = 0;
// performing swap of numbers
$temp = $num1;
$num1 = $num2;
$num2 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Before Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo “ ”;
// declaring temporary variable to be zero
$temp = 0;
// performing swap of numbers
$temp = $num1;
$num1 = $num2;
$num2 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Before Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo “ ”;
// declaring temporary variable to be zero
$temp = 0;
// performing swap of numbers
$temp = $num1;
$num1 = $num2;
$num2 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Before Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo “ ”;
// declaring temporary variable to be zero
$temp = 0;
// performing swap of numbers
$temp = $num1;
$num1 = $num2;
$num2 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo “ ”;
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>
Saída :
2. Trocando dois números sem variável temporária
Código:
<_?php// Example of swapping of two numbers without using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statemnt print the variables before swapping two numbers
echo "
"."Swap done without using temparory variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
$num1 = $num1 - $num2;
$num2 = $num1 + $num2;
$num1 = $num2 - $num1;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers without using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statemnt print the variables before swapping two numbers
echo "
"."Swap done without using temparory variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
$num1 = $num1 - $num2;
$num2 = $num1 + $num2;
$num1 = $num2 - $num1;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers without using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statemnt print the variables before swapping two numbers
echo "
"."Swap done without using temparory variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
$num1 = $num1 - $num2;
$num2 = $num1 + $num2;
$num1 = $num2 - $num1;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers without using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statemnt print the variables before swapping two numbers
echo "
"."Swap done without using temparory variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
$num1 = $num1 - $num2;
$num2 = $num1 + $num2;
$num1 = $num2 - $num1;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers without using a temporary variable
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statemnt print the variables before swapping two numbers
echo "
"."Swap done without using temparory variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
$num1 = $num1 - $num2;
$num2 = $num1 + $num2;
$num1 = $num2 - $num1;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>
Resultado:
3. Troca de dois números usando uma função como list () com array ()
Código:
<_?php// Example of swapping of two numbers using list() with array()
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Swap done without using predefined functions";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
list($num1, $num2) = array($num2, $num1);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using list() with array()
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Swap done without using predefined functions";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
list($num1, $num2) = array($num2, $num1);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using list() with array()
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Swap done without using predefined functions";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
list($num1, $num2) = array($num2, $num1);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using list() with array()
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Swap done without using predefined functions";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
list($num1, $num2) = array($num2, $num1);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>// Example of swapping of two numbers using list() with array()
// Declaring two variables
$num1 = 100;
$num2 = 200;
// using echo statement print the variables before swapping two numbers
echo "
"."Swap done without using predefined functions";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo " ";
// performing swap of numbers
list($num1, $num2) = array($num2, $num1);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
?>
Resultado:
Como trocar três números em PHP?
Existem duas maneiras de trocar números. Esses números mantêm valores numéricos.
- Trocando três números por uma variável temporária.
- Trocar três números sem uma variável temporária.
1. Trocando três números usando variável temporária
Agora que aprendemos a troca de dois números, de maneira semelhante, aprendemos a troca de três números agora. O exemplo a seguir demonstra como uma variável temporária (temp) é usada para trocar três números.
Código:
<_?php// Example of swapping three numbers using temporary variable
// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$temp = $num1;
$num1 = $num2;
$num2 = $num3;
$num3 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Example of swapping three numbers using temporary variable
// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$temp = $num1;
$num1 = $num2;
$num2 = $num3;
$num3 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Example of swapping three numbers using temporary variable
// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$temp = $num1;
$num1 = $num2;
$num2 = $num3;
$num3 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Example of swapping three numbers using temporary variable
// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$temp = $num1;
$num1 = $num2;
$num2 = $num3;
$num3 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Example of swapping three numbers using temporary variable
// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$temp = $num1;
$num1 = $num2;
$num2 = $num3;
$num3 = $temp;
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>
Resultado:
2. Trocando três números sem usar variáveis temporárias
A lógica aqui é calcular a soma total e atribuí-la a uma variável $ num1.
E depois,
calcule o valor de $ num1, atribua esse valor a $ num2,
calcule o valor de $ num2, atribua esse valor a $ num3,
calcule o valor de $ num3 e atribua esse valor a $ num1 novamente.
Código:
<_?php// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$num1 = $num1 + $num2 + $num3;
$num2 = $num1 - ($num2 + $num3);
$num3 = $num1 - ($num2 + $num3);
$num1 = $num1 - ($num2 + $num3);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$num1 = $num1 + $num2 + $num3;
$num2 = $num1 - ($num2 + $num3);
$num3 = $num1 - ($num2 + $num3);
$num1 = $num1 - ($num2 + $num3);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$num1 = $num1 + $num2 + $num3;
$num2 = $num1 - ($num2 + $num3);
$num3 = $num1 - ($num2 + $num3);
$num1 = $num1 - ($num2 + $num3);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$num1 = $num1 + $num2 + $num3;
$num2 = $num1 - ($num2 + $num3);
$num3 = $num1 - ($num2 + $num3);
$num1 = $num1 - ($num2 + $num3);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>// Declaring three variables
$num1 = 100;
$num2 = 200;
$num3 = 300;
// using echo statement print the variables before swapping three numbers
echo "
"."Swap done without using temporary variable";
echo " ";
echo "
"."Before Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
echo " ";
// performing swap of numbers
//assign first number the total of three numbers
$num1 = $num1 + $num2 + $num3;
$num2 = $num1 - ($num2 + $num3);
$num3 = $num1 - ($num2 + $num3);
$num1 = $num1 - ($num2 + $num3);
//using the echo statement print the variables after swapping the numbers
echo "
"."After Swap";
echo " ";
echo "
"."Value of first number is = ". $num1;
echo "
"."Value of second number is = ". $num2;
echo "
"."Value of third number is = ". $num3;
?>
Resultado:
Conclusão
Espero que este artigo seja útil para todos os programadores que desejam aprender a troca de números. Este artigo possui duas trocas de dois e três números com exemplos apropriados. Esses exemplos, se praticados, ajudarão você a aprender o conceito e a lembrar a lógica também.
Artigos recomendados
Este é um guia para trocar no PHP. Aqui discutimos como trocar dois ou três números com ou sem o uso de variáveis temporárias junto com seus exemplos. Você também pode consultar os seguintes artigos para saber mais:
- Sessões em PHP
- Padrões em PHP
- Cookie em PHP
- Sobrecarga em PHP
- Sobrecarga em Java
- Sobrecarga de Python