View Code of Problem 73

    #include<iostream>

     
    using namespace std;
     
    int main()
    {
      
    	int n;
		cin>>n;
      	int x=1;
      	n--;
      	while(n--)
            {
            	x=(x+1)*2;
            }
      	cin>>x;
    	return 0;
    }