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int raise To Power(int number, int power){
int result = number * number;
 return raise ToPower(result, power - 1);


What I have tried:

i tried to rename the function and tried to remove spaces
Posted
Updated 22-Aug-19 10:34am
Comments
KarstenK 23-Aug-19 4:48am
   
The compiler had already talked to you. Learn to understand it. He is a gentle but harsh friend.
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Solution 1

Quote:
What is wrong with this function?

A few things:
- 'raise To Power' is not a proper function name, spaces are not allowed in C/C++ or other languages.
- 'raise ToPower' names must be exactly the same in definition and usage, C is case sensitive.
- your function is remotely recursive, but it is missing the ending condition. (see how recursion works)
[Update]
This
int result = number * number;

is repeatedly squaring the value, so for initial value of 2 the values of result are 4 => 16 => 256 ...
Advice: Learn debugger as soon as possible, it is an incredible learning tool.

Your code do not behave the way you expect, or you don't understand why !

There is an almost universal solution: Run your code on debugger step by step, inspect variables.
The debugger is here to show you what your code is doing and your task is to compare with what it should do.
There is no magic in the debugger, it don't know what your code is supposed to do, it don't find bugs, it just help you to by showing you what is going on. When the code don't do what is expected, you are close to a bug.
To see what your code is doing: Just set a breakpoint and see your code performing, the debugger allow you to execute lines 1 by 1 and to inspect variables as it execute.
Debugger - Wikipedia, the free encyclopedia[^]

Mastering Debugging in Visual Studio 2010 - A Beginner's Guide[^]
Basic Debugging with Visual Studio 2010 - YouTube[^]

1.11 — Debugging your program (stepping and breakpoints) | Learn C++[^]

The debugger is here to only show you what your code is doing and your task is to compare with what it should do.
   
v3
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Solution 2

A recursive function must have a recursive return statement but it must also have a non- recursive return statement to end the recursion.

static int raiseToPower(int n, int power)
      {
          // non-recursive call
          if (power == 0) return 1;
           //recursive call
          return raiseToPower(n, power - 1) * n;
      }

Say we want the answer to 2 raised to the power of 3. The function is called with n=2 and power=3.The function's logic goes like this, I know the answer when power=0 it's 1 and but I don't know the answer when power=3 without first calling the function with power=2 and multiplying that result by n. So the function is called a second time and on that occasion power=2. The same logic applies to the third call to the function. On the fourth call, power=0 and that function returns 1 and ends the recursive calls. The third call now receives the 1 and returns 1*2=2. The second call then receives the 2 and returns 2*2=4. The first call then receives 4, multiplies it by 2 and returns 8. All calls have now returned a result and the method calls end.

   

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