假设我们有四个变量a，b，c，d，并且我们想要以以下方式执行这些变量的交换
a = b，b = c，c = d，d = a
不使用任何其他第五或临时变量
解决方案 ：
步骤1.交换a和b，而不使用任何其他变量
a = a + b
b = a – b
a = a – b
步骤2.交换b和c，而不使用任何其他变量
b = b + c
c = b – c
b = b – c
步骤3.交换c和d，而不使用任何其他变量
c = c + d
d = c – d
c = c – d
例子：
Input : a = 1, b = 2, c = 3, d = 4
Output :After swapping
a = 2, b = 3, c = 4, d = 1
Input :a = 6, b = 9, c = 10, d = 50
Output : After swapping : a = 9, b = 10, c = 50, d = 6
先决条件：交换两个没有临时变量的变量，交换三个没有临时变量的变量
CPP
// CPP program to swap 4 variables without
// using temporary variable.
#include
using namespace std;
void swap(int a, int b, int c, int d)
{
// swapping a and b variables
a = a + b;
b = a - b;
a = a - b;
// swapping b and c variables
b = b + c;
c = b - c;
b = b - c;
// swapping c and d variables
c = c + d;
d = c - d;
c = c - d;
cout << "values after swapping are : " << endl;
cout << "a = " << a << endl;
cout << "b = " << b << endl;
cout << "c = " << c << endl;
cout << "d = " << d << endl;
}
// Driver code
int main()
{
// initialising variables
int a = 1;
int b = 2;
int c = 3;
int d = 4;
cout << "Values before swapping are :" << endl;
cout << "a = " << a << endl;
cout << "b = " << b << endl;
cout << "c = " << c << endl;
cout << "d = " << d << endl << endl;
// Function call
swap(a, b, c, d);
return 0;
} Java
// Java program to swap 4 variables
// without using temporary variable.
class GFG {
static void swap(int a, int b, int c, int d)
{
// swapping a and b variables
a = a + b;
b = a - b;
a = a - b;
// swapping b and c variables
b = b + c;
c = b - c;
b = b - c;
// swapping c and d variables
c = c + d;
d = c - d;
c = c - d;
System.out.println("values after "
+ "swapping are : ");
System.out.println("a = " + a);
System.out.println("b = " + b);
System.out.println("c = " + c);
System.out.println("d = " + d);
}
// Driver code
public static void main(String[] args)
{
// initialising variables
int a = 1;
int b = 2;
int c = 3;
int d = 4;
System.out.println("values before "
+ "swapping are : ");
System.out.println("a = " + a);
System.out.println("b = " + b);
System.out.println("c = " + c);
System.out.println("d = " + d);
System.out.println("");
// Function call
swap(a, b, c, d);
}
}
// This code is contributed by Smitha.Python3
# Python 3 program to swap 4 variables
# without using temporary variable.
def swap(a, b, c, d):
# swapping a and b variables
a = a + b
b = a - b
a = a - b
# swapping b and c variables
b = b + c
c = b - c
b = b - c
# swapping c and d variables
c = c + d
d = c - d
c = c - d
print("values after swapping are : ")
print("a = ", a)
print("b = ", b)
print("c = ", c)
print("d = ", d)
# Driver code
# initialising variables
a = 1
b = 2
c = 3
d = 4
print("values before swapping are : ")
print("a = ", a)
print("b = ", b)
print("c = ", c)
print("d = ", d)
print("")
# Function call
swap(a, b, c, d)
# This code is contributed by Smitha.C#
// C# program to swap 4 variables
// without using temporary variable.
using System;
class GFG {
static void swap(int a, int b, int c, int d)
{
// swapping a and b variables
a = a + b;
b = a - b;
a = a - b;
// swapping b and c variables
b = b + c;
c = b - c;
b = b - c;
// swapping c and d variables
c = c + d;
d = c - d;
c = c - d;
Console.WriteLine("values after "
+ "swapping are : ");
Console.WriteLine("a = " + a);
Console.WriteLine("b = " + b);
Console.WriteLine("c = " + c);
Console.WriteLine("d = " + d);
}
// Driver Code
public static void Main()
{
// initialising variables
int a = 1;
int b = 2;
int c = 3;
int d = 4;
Console.WriteLine("values before "
+ "swapping are : ");
Console.WriteLine("a = " + a);
Console.WriteLine("b = " + b);
Console.WriteLine("c = " + c);
Console.WriteLine("d = " + d);
Console.WriteLine("");
// Function call
swap(a, b, c, d);
}
}
// This code is contributed by Smitha.PHP
输出
Values before swapping are :
a = 1
b = 2
c = 3
d = 4
values after swapping are :
a = 2
b = 3
c = 4
d = 1