Dylan has grandparents who believe in "planning for the future" instead of giving toys for birthdays...

Code

Using for loop

#include<iostream>
using namespace std;

int main()
{
   int i, amount=0;

   //using for loop

   for (int i = 1; i <= 21; i++)
   {
       amount += (i * 10);
   }
   cout << "Using for loop" << endl;
   cout << "Dylan's account at the end of the 21 year: $" << amount << endl;

   system("pause");
   return 0;
}

output

using while loop

#include<iostream>
using namespace std;

int main()
{
   int i, amount = 0;
   //using while loop
   i = 1; amount = 0;
   while (i <= 21)
   {
       amount += (i * 10);
       i++;
   }

   cout << "\n\nUsing while loop" << endl;
   cout << "Dylan's account at the end of the 21 year: $" << amount << endl;

   system("pause");
   return 0;
}

using fo while

#include<iostream>
using namespace std;

int main()
{
   int i, amount = 0;
  
   i = 1; amount = 0;
  

   //using do while
   do
   {
       amount += (i * 10);
       i++;
   } while (i <= 21);
   cout << "\n\nUsing do while loop" << endl;
   cout << "Dylan's account at the end of the 21 year: $" << amount << endl;
   system("pause");
   return 0;
}

output

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