So what happens when you want to change each of the values within a vector?

You can use a for loop!

For example, suppose we have an int vector that looks like this:


You can write a for loop that iterates from 0 to vector.size(). And here’s the cool part: you can use the counter of the for loop as the index! Woah.

for (int i = 0; i < vector.size(); i++) { vector[i] = vector[i] + 10; }

This will change the vector to:


Here, we incremented i from 0 to vector.size(), which is 3. During each iteration, we are adding 10 to the element at position i:

  • When i = 0, we added 10 to vector[0]
  • When i = 1, we added 10 to vector[1]
  • When i = 2, we added 10 to vector[2]



In the code editor, there is a double vector named delivery_order that is storing the prices of some food items.

There is also a double variable named total that’s already declared and initialized.

Write a for loop that iterates through the delivery_order vector (from 0 to delivery_order.size()). And add each order to total during each iteration.


Output the final total using std::cout.

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