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Define a getStandardDeviation() function with the specification and prototype shown below:

// Calculate the population standard deviation of the scores
// That means...
// 1) For each score i, add pow(scores[i] - mean,2) to a running sum.
// 2) divide sum by the number of scores. That's the variance.
// 3) Return the square root of the variance.
// Assume that numScores > 0
double getStandardDeviation( double scores[], int numScores, double mean) ;

Here is the driver (main()) used to test my function.

#include <iostream>
 #include <iomanip>
 #include <cmath>
 using namespace std;

const int MAX_SCORES = 10; // Maximum number of scores

double getStandardDeviation( double scores[], int numScores, double mean) ;

int main() {
    double scores[MAX_SCORES];
    int scoreCount, skip;
    cin >> scoreCount;
    cin >> skip;
    scoreCount = min(scoreCount, MAX_SCORES);
    int i;
    for (i = 0; i < scoreCount; i++)
       scores[i] = i*skip;
    double mean = (i-1)*skip/2.0; // e.g. mean of 0,1,2,3,4,5 is (6-1)/2.0 = 2.5
    cout << fixed << setprecision(2);
    cout << getStandardDeviation(scores, scoreCount,mean) << endl;
    return 0;
 } 

Here is my solution:

double getStandardDeviation( double scores[], int numScores, double mean)
{
    int sum;
    int variance;
    for(int i = 0; i < numScores; i++)
    {
        sum += pow(scores[i] - mean,2);
    }
    variance = sum / numScores;
    return sqrt(variance);
}

Here is my output:

Input: 2 1
Output: 0.00

Here is the expected output:

Input: 2 1
Output: 0.50

Am I doing the calculation correctly? What lines of code should I change?

Am I doing the calculation correctly? What lines of code should I change?

Line 3 and 4:

 int sum;
 int variance;

change them to double.

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