Answer to question 10A-2

Answer to Question 10A-2

We want to initialize p = 1 and to multiply p by x a total of n times. From the preceding problem, we know how to perform something n times. Here is a skeleton that repeats STEP n times.

  int i = 1;
  while(i <= n)
  {
    STEP
    i++;
  }

Now lets add initialization of p and replace STEP by a statement that multiplies p by x. The parts in red have been added.

  int p = 1;
  int i = 1;
  while(i <= n)
  {
    p *= x;
    i++;
  }

That loop ends with p = xⁿ. Let's wrap that up into a function.

  // power(x,n) returns x to power n.
  // Requirements: n >= 0 and x != 0.

  int power(int x, int n)
  {
    int p = 1;
    int i = 1;
    while(i <= n)
    {
      p *= x;
      i++;
    }
    return p;
  }