- To swap 2 numbers without using 3rd variable
User Input
1st number: 3
2nd number: 5
After Swap, Output:
1st number : 5
2nd number : 3
#include <iostream>
using namespace std;
int main() {
int n1,n2;
cout<<"Enter 1st number: ";
cin>>n1;
cout<<"Enter 2nd number: ";
cin>>n2;
n1=n1+n2;
n2=n1-n2;
n1=n1-n2;
cout<<"After Swap"<<endl;
cout<<"1st number :"<<n1<<"\n2nd number :"<<n2;
return 0;
}
Enter 1st number : 7 Enter 2nd number : 15 After Swap 1st number : 15 2nd number : 7Program
Here we are adding both values into one then used some maths
//Lets take n1=7, n2=3;
n1=n1+n2; //n1=7+3=10
n2=n1-n2; //n2=10-3=7
n1=n1-n2; //n1=10-7=3
//Finally you swaped & get n1=3, n2=7;
Concept