CODEWITHSUNDEEP
c++for-loop
mrtammy
mrtammy

Reputation: 217

How do I increase the result presented by my "for loop"?

for (int j=1; j<=120; j++){

Pop=10180000;            //Pop = Population //
Increase=Pop*0.0118;
Pop=Increase+Pop;


cout<< Increase <<endl;
cout<< Pop <<endl;

}

I am really new here, sorry if I made a mistake. I am suppose to find out the amount of population (10.18mil) for 120 months with the increase of 1.18% every month.

I managed to find the first month but my for loop repeats the same result every line for the next 120 lines.

Upvotes: 1

Views: 67

Answers (2)

paxdiablo
paxdiablo

Reputation: 881223

Your problem is that you're setting the initial value of the population every iteration of the loop. You should be doing that once before the loop starts.

You can also simplify the calculation since a 1.18% increase can be achieved by just multiplying by 1.0118. That gives you something like:

int Pop = 10180000;
for (int i = 1; i <= 120; i++)
    Pop = Pop * 1.0118;
cout << Pop << endl;

Of course, if you were writing real code, you may want to factor out the functionality so that it could be re-used easily:

int increaseValue(
    int          value,
    double       ratePerPeriod,
    unsigned int periodCount
) {
    for (unsigned int i = 0; i < periodCount; i++)
        value *= (ratePerPeriod / 100.0 + 1.0);
    return value;
}

:

cout << increaseValue(10180000, 1.18, 120) << endl;

Upvotes: 1

mammothb
mammothb

Reputation: 16

In your code, you re-initialize Pop as 10180000 at the start of each iteration. You should move it above the loop so that its value does not get reset at each iteration.

Pop=10180000;            //Pop = Population //
for (int j = 1; j <= 120; j++) {
  Increase=Pop*0.0118;
  Pop=Increase+Pop;

  cout<< Increase <<endl;
  cout<< Pop <<endl;
}

Upvotes: 0

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