Having trouble with pointers in C++ - visual-c++

Question

I am trying to access an array from inside of a function, but I get the
"Error C2065 'i': undeclared identifier." I know that I am making a mistake with the pointer. I was able to pull information from the array in the function below the one I'm having issues with, so I'm not sure why I am unable to do the same thing here. Thank you for your time.
#include <iostream>
#include <cmath>
using namespace std;
double mean(int size, int* numbers);
double sDeviation(int numOfScores, int average, int* scores);
int histogram(int numOfScores, int* scores); //<<<This is what I'm having trouble with
int main()
{
int count = 0;
int scores[100];
while (true)
{
int scoreToBeEntered;
cout << "Please enter a score: ";
cin >> scoreToBeEntered;
if(scoreToBeEntered == NULL)
cout << "No value entered" << endl;
else if(scoreToBeEntered != -1)
scores[count++] = scoreToBeEntered;
else
break;
}
for(int i = 9; i >= 0; i--)
cout << i << "|" << endl;
cout << "SD: " << sDeviation(count, mean(count, scores), scores) << endl;
system("pause");
return 0;
}
int histogram(int numOfScores, int* scores)//this is where the issue starts
{
int* bins = new int[10];
for(int i = 0; i < numOfScores; i++);
if(scores[i] >= 90) //<<<<This is the undeclared "i"
{
bins[9]++;
}
}
double sDeviation(int numOfScores, int average, int* scores)
{
double deviation = 0;
for (int i = 0; i < numOfScores; i++)
deviation += pow(scores[i] - average, 2);
return sqrt(deviation / numOfScores);
}
double mean(int size, int* numbers)
{
double sum = 0;
for (int i = 0; i < size; i++)
sum += numbers[i];
return sum / size;
}