I'm having problems moving the first input of my array to the end so that I can compute the average of the Window number of inputs. I have to use an array (not a matrix) to compute the moving average of weights. Question: if I set my number of weights to 5, input 5 weights, and then execute the arithmetic I get the correct average for the 1st day, however, everyday after that is incorrect. Can anyone lend guidance here and/or point me to a program or website that will allow me to execute my code line for line so that I can trouble shoot this problem more effectively. Thanks!
#include <iostream>
#include <cstdlib>
using namespace std;
const int MAX_NUM_WEIGHTS = 50;
// Function prototypes:
void movingAverage(int& numWeights, int weightArray[], int& Window);
int main()
{
int numWeights, Window;
int weightArray[MAX_NUM_WEIGHTS];
movingAverage(numWeights, weightArray, Window);
return 0;
}
void movingAverage(int& numWeights, int weightArray[], int& Window)
{
int i = 0, j = 0, day = 0, sum = 0, temp;
double avg;
cout << "Enter the number of weights: ";
cin >> numWeights;
cout << endl;
cout << "Enter the weights: ";
for(i = 0; i < numWeights; i++) {
cin >> weightArray[i];
}
cout << "Enter the length of the window: ";
cin >> Window;
cout << endl << endl;
while(k < numWeights - 1) {
for(j = 0; j < Window; j++) {
sum += weightArray[j];
}
avg = static_cast<double>(sum) / Window;
day = day + 1;
cout << day << ": " << avg << endl;
int temp = weights[i];
weights[i] = weights[numWeights];
if(k >= (numWeights - 1)) {
break;
}
}
}
Related
`
#include <iostream>
#include <iomanip>
using namespace std;
void getGrades(double g[], const int SIZE)
{
cout << "Please enter " << SIZE << " grades:" << endl;
for(int i = 0; i < SIZE; i++)
{
cin >> g[i];
}
}
double getAverage(double g[], const int SIZE)
{
int total = 0;
for(int i = 0; i < SIZE; i++)
{
total += g[i];
}
return total/SIZE;
}
void findDropInfo(double g[], const int SIZE, int &lowest, double average)
{
int total = 0;
lowest = g[0];
for(int i = 1; i < SIZE; i++)
{
if (lowest > g[i]) {
lowest = g[i];
}
}
average = (total - lowest)/SIZE;
return average;
}
void printData(double g[], int lowest, double average, double avg_before)
{
cout << "The 5 grades entered by the user are:" << endl;
cout << g[];
cout << "Grade dropped: " << lowest << endl;
cout << "Final Average: " << average << endl;
cout << "Average before drop: " << avg_before << endl;
}
// TODO: Complete the function definitions
int main()
{
const int SIZE = 5;
double grades[SIZE];
int lowest;
double avg,
avgBeforeDrop;
// TODO: Add function calls
getGrades(grades[SIZE], SIZE);
getAverage(grades[SIZE], SIZE);
findDropInfo(grades[SIZE], SIZE, lowest, avg);
printData(grades[SIZE], lowest, avg, avgBeforeDrop);
return 0;
}
`
Whenever I run the program, I get multiple errors saying there's no matching candidate function. I'm not sure if the problems are in the functions themselves or in the function calls, but from what I know the functions themselves should be fine. I'm also told there's an expected expression in g[] but I' not sure what's wrong there either, as it's meant to be empty.
Most issues have already been resolved in the comments, but note: cout << g[] does not print the elements of g.
The way to do this is
char separator = /* the character you want to use to separate the printed elements of g */
for (int i = 0; i < SIZE; i++)
{
cout << g[i] << separator;
}
if (separator != '\n') cout << '\n'; //this is to put the next print on the next line
I would put this as a comment but I don't have enough reputation :|
I finished this code homework assignment tonight. I thought I was done, but I just realized that my "Average" value is coming out wrong with certain values. For example: When my professor entered the values 22, 66, 45.1, and 88 he got an "Average" of 55.27. However, when I enter those values in my program, I get an "Average" of 55.25. I have no idea what I am doing wrong. I was pretty confident in my program until I noticed that flaw. My program is due at midnight, so I am clueless on how to fix it. Any tips will be greatly appreciated!
Code Prompt: "Write a program that dynamically allocates an array large enough to hold a user-defined number of test scores. Once all the scores are entered, the array should be passed to a function that sorts them in ascending order. Another function should be called that calculates the average score. The program should display the sorted list of scores and averages with appropriate headings. Use pointer notation rather than array notation whenever possible."
Professor Notes: The book only states, "Input Validation: Do not accept negative numbers for test scores." We also need to have input validation for the number of scores. If it is negative, including 0, the program halts, we should consider this situation for 'counter' not to be negative while we have a loop to enter numbers. So negative numbers should be rejected for the number of scores and the values of scores.
Here is my code:
#include <iostream>
#include <iomanip>
using namespace std;
void showArray(double* array, int size);
double averageArray(double* array, int size);
void orderArray(double* array, int size);
int main()
{
double* scores = nullptr;
int counter;
double numberOfScores;
cout << "\nHow many test scores will you enter? ";
cin >> numberOfScores;
if (numberOfScores < 0) {
cout << "The number cannot be negative.\n"
<< "Enter another number: ";
cin >> numberOfScores;
}
if (numberOfScores == 0) {
cout << "You must enter a number greater than zero.\n"
<< "Enter another number: ";
cin >> numberOfScores;
}
scores = new double[numberOfScores];
for (counter = 0; counter < numberOfScores; counter++) {
cout << "Enter test score " << (counter + 1) << ": ";
cin >> *(scores + counter);
if (*(scores + counter) < 0) {
cout << "Negative scores are not allowed. " << endl
<< "Enter another score for this test : ";
cin >> *(scores + counter);
}
}
orderArray(scores, counter);
cout << "\nThe test scores in ascending order, and their average, are: " << endl
<< endl;
cout << " Score" << endl;
cout << " -----" << endl
<< endl;
showArray(scores, counter);
cout << "\nAverage Score: "
<< " " << averageArray(scores, counter) << endl
<< endl;
cout << "Press any key to continue...";
delete[] scores;
scores = nullptr;
system("pause>0");
}
void orderArray(double* array, int size)
{
int counterx;
int minIndex;
int minValue;
for (counterx = 0; counterx < (size - 1); counterx++) {
minIndex = counterx;
minValue = *(array + counterx);
for (int index = counterx + 1; index < size; index++) {
if (*(array + index) < minValue) {
minValue = *(array + index);
minIndex = index;
}
}
*(array + minIndex) = *(array + counterx);
*(array + counterx) = minValue;
}
}
double averageArray(double* array, int size)
{
int x;
double total{};
for (x = 0; x < size; x++) {
total += *(array + x);
}
double average = total / size;
return average;
}
void showArray(double* array, int size)
{
for (int i = 0; i < size; i++) {
cout << " " << *(array + i) << endl;
}
}
I try to start my answers with a brief code review:
#include <iostream>
#include <iomanip>
using namespace std; // Bad practice; avoid
void showArray(double* array, int size);
double averageArray(double* array, int size);
void orderArray(double* array, int size);
int main()
{
double* scores = nullptr;
int counter;
double numberOfScores;
cout << "\nHow many test scores will you enter? ";
cin >> numberOfScores;
// This is not input validation, I can enter two consecutive bad values,
// and the second one will be accepted.
if (numberOfScores < 0) {
// Weird formatting, this blank line
cout << "The number cannot be negative.\n"
<< "Enter another number: ";
cin >> numberOfScores;
}
// The homework, as presented, doesn't say you have to treat 0 differently.
if (numberOfScores == 0) {
cout << "You must enter a number greater than zero.\n"
<< "Enter another number: ";
cin >> numberOfScores;
}
scores = new double[numberOfScores];
// Declare your loop counter in the loop
for (counter = 0; counter < numberOfScores; counter++) {
cout << "Enter test score " << (counter + 1) << ": ";
cin >> *(scores + counter);
if (*(scores + counter) < 0) {
cout << "Negative scores are not allowed. " << endl
<< "Enter another score for this test : ";
cin >> *(scores + counter);
}
}
orderArray(scores, counter); // Why not use numberOfScores?
cout << "\nThe test scores in ascending order, and their average, are: " << endl
<< endl;
cout << " Score" << endl;
cout << " -----" << endl
<< endl;
showArray(scores, counter); // Same as above.
cout << "\nAverage Score: "
<< " " << averageArray(scores, counter) << endl
<< endl;
cout << "Press any key to continue...";
delete[] scores;
scores = nullptr;
system("pause>0"); // Meh, I suppose if you're on VS
}
void orderArray(double* array, int size)
{
int counterx;
int minIndex;
int minValue; // Unnecessary, and also the culprit
// This looks like selection sort
for (counterx = 0; counterx < (size - 1); counterx++) {
minIndex = counterx;
minValue = *(array + counterx);
for (int index = counterx + 1; index < size; index++) {
if (*(array + index) < minValue) {
minValue = *(array + index);
minIndex = index;
}
}
*(array + minIndex) = *(array + counterx);
*(array + counterx) = minValue;
}
}
double averageArray(double* array, int size)
{
int x;
double total{};
for (x = 0; x < size; x++) {
total += *(array + x);
}
double average = total / size;
return average;
}
void showArray(double* array, int size)
{
for (int i = 0; i < size; i++) {
cout << " " << *(array + i) << endl;
}
}
When you are sorting your array, you keep track of the minValue as an int and not a double. That's why your average of the sample input is incorrect. 45.1 is truncated to 45 for your calculations. You don't need to keep track of the minValue at all. Knowing where the minimum is, and where it needs to go is sufficient.
But as I pointed out, there are some other serious problems with your code, namely, your [lack of] input validation. Currently, if I enter two consecutive bad numbers, the second one will be accepted no matter what. You need a loop that will not exit until a good value is entered. It appears that you are allowed to assume that it's always a number at least, and not frisbee or any other non-numeric value.
Below is an example of what your program could look like if your professor decides to teach you C++. It requires that you compile to the C++17 standard. I don't know what compiler you're using, but it appears to be Visual Studio Community. I'm not very familiar with that IDE, but I imagine it's easy enough to set in the project settings.
#include <algorithm>
#include <iomanip>
#include <iostream>
#include <numeric>
#include <string>
#include <vector>
// Assumes a number is always entered
double positive_value_prompt(const std::string& prompt) {
double num;
std::cout << prompt;
do {
std::cin >> num;
if (num <= 0) {
std::cerr << "Value must be positive.\n";
}
} while (num <= 0);
return num;
}
int main() {
// Declare variables when you need them.
double numberOfScores =
positive_value_prompt("How many test scores will you enter? ");
std::vector<double> scores;
for (int counter = 0; counter < numberOfScores; counter++) {
scores.push_back(positive_value_prompt("Enter test score: "));
}
std::sort(scores.begin(), scores.end());
for (const auto& i : scores) {
std::cout << i << ' ';
}
std::cout << '\n';
std::cout << "\nAverage Score: "
<< std::reduce(
scores.begin(), scores.end(), 0.0,
[size = scores.size()](auto mean, const auto& val) mutable {
return mean += val / size;
})
<< '\n';
}
And here's an example of selection sort where you don't have to worry about the minimum value. It requires that you compile to C++20. You can see the code running here.
#include <iostream>
#include <random>
#include <vector>
void selection_sort(std::vector<int>& vec) {
for (int i = 0; i < std::ssize(vec); ++i) {
int minIdx = i;
for (int j = i + 1; j < std::ssize(vec); ++j) {
if (vec[j] < vec[minIdx]) {
minIdx = j;
}
}
int tmp = vec[i];
vec[i] = vec[minIdx];
vec[minIdx] = tmp;
}
}
void print(const std::vector<int>& v) {
for (const auto& i : v) {
std::cout << i << ' ';
}
std::cout << '\n';
}
int main() {
std::mt19937 prng(std::random_device{}());
std::uniform_int_distribution<int> dist(1, 1000);
std::vector<int> v;
for (int i = 0; i < 10; ++i) {
v.push_back(dist(prng));
}
print(v);
selection_sort(v);
print(v);
}
I opted not to give your code the 'light touch' treatment because than I would have done your homework for you, and that's just not something I do. However, the logic shown should still be able to guide you toward a working solution.
I wrote a code to manage a coffee machine,
I have a function findC that finds the cheapest capsule in the capsule array
a different function of mine findVP that is supposed to use the findC function's output as variables. however, when I pass the variables mp, ind = findC(prices_copy, quantities_copy, SIZE);
and print them it passes them as 0;
but the 2nd cout : cout << findC(prices_copy, quantities_copy, SIZE); prints the correct output.
why is this ? and how can I pass the output of the function to another
/******************************************************************************
Online C++ Compiler.
Code, Compile, Run and Debug C++ program online.
Write your code in this editor and press "Run" button to compile and execute it.
*******************************************************************************/
// Example program
#include <iostream>
#include <string>
#include <bits/stdc++.h>
using namespace std;
#define SLEEVE 10
#define SIZE 10
#define N 5
#define BUDGET 70
//int CapsuleKind[10] = {"JOE","MAC","NES","jamaica","brazil","columbia","MOJO","CLUB","JHON","COF"};
float findMostExpensiveCapsule( float prices[], int size ) // 1
{
float max = prices[0];
int count = 0;
for(int i = 1; i < size; i++)
{
if (prices[i] > max)
{
max = prices[i];
}
}
cout << "The maximum price " << max << " is found on indexes: " ;
for (int i = 0; i < size; i++)
{
if (prices[i] == max)
{
cout << i << " ";
count++;
}
}
cout << endl;
cout << "The maximum number appears " << count << " times." << endl;
return max;
}
int findStrongestCapsuleInStock( int quantities[], int size, int sleeve ) // 2
{
return 0;
}
void SellCapsules( int quantities[], int Qty, int index) // 10
{
quantities[index] = quantities[index] - Qty;
cout << "SOLD " << Qty << " capsules to the Customer, the total now is: " << quantities[index] << endl;
}
float findC( float prices[],int quantities[], int size ) // 9
{
float min = 99999;
int count = 0;
float index=0;
//sort(prices, arr + n);
for(int i = 0; i < size; i++)
{
if (quantities[i] >= SLEEVE)
{
if(prices[i] < min){
min = prices[i];
index= i;
}
else continue;
}
}
cout <<"the minimum price is : " << min << " ---- the index is : " << index << endl;
return min, index;
}
void findCheapestSleeve( float prices[],int quantities[], int size )
{
float min = prices[0];
int count = 0;
int index=0;
for(int i = 0; i < size; i++)
{
if (prices[i] < min)
{
if(quantities[i] > SLEEVE){
min = prices[i];
index= i;
}
else continue;
}
}
cout <<"the minimum price is : " << min << " ---- the index is : " << index << endl;
}
void showAllCapsulesInStock( int quantities[], float prices[], int size, int sleeve) // 3
{
for (int i = 0; i < size; i++)
{
cout << "capsule kind: " << i << " ---- sleeves available : " << (quantities[i]/sleeve) << " ---- price(for 1 sleeve): " << (prices[i]*sleeve)<< endl;
}
}
float findVP( float prices[], int quantities[], int size, float nis, int sleeve ) //4
{
float mp=0;
float ind =0;
float prices_copy[size];
int quantities_copy[size];
for(int i=0; i<size; i++){
prices_copy[i] = prices[i];
quantities_copy[i] = quantities[i];
}
mp, ind = findC(prices_copy, quantities_copy, SIZE);
cout << "The lowest price sleeve is: " << mp * 10 << " --- the capsule kind is: " << ind <<endl;
cout << findC(prices_copy, quantities_copy, SIZE);
}
void findValueForMoneyPackage( float prices[], int quantities[], int size, float nis, int sleeve )
{
int sleeve_num[size];
float sleeve_price[size];
float min=0;
int index = 0;
int counter=0;
float quant = 0;
for (int i=0; i < size; i++)
{
sleeve_num[i] = (quantities[i]/sleeve);
sleeve_price[i] = (prices[i] * sleeve);
}
//min, quant = findCheapestSleeve(sleeve_price, quantities, 10);
cout << "the cheapest sleeve costs : " << min << " and its of kind :" << quant << endl;
}
void addMoreCapsules( int quantities[], int size ) // 5
{
char answer;
int plus;
for (int i = 0; i < size; i++)
{
cout << "do you want to add capsules to capsule kind " << i << "? (Y/N) " << endl;
cin >> answer;
if (answer == 'Y')
{
cout << "How many capsules do you want to add (inter a number) " << endl;
cin >> plus;
if (plus > 0)
{
quantities[i] = quantities[i] + plus;
cout << "Added " << plus << " capsules to the inventory, the total now is: " << quantities[i] << endl;
}
}
else
{
continue;
}
}
}
// Driver Code
int main()
{
bool flag = false;
int option;
float prices[] = { 1.2, 2.2, 2.5, 1.7, 2.2, 3, 2.8, 2.5, 2.9, 3.7 };
int quantities[] = { 14, 22, 25, 13, 22, 33, 50, 60, 33, 25 };
while (flag != true)
{
cout << "Please choose an option , has to be a number 1-6" << endl;
cin >> option;
if (option == 1)
{
findMostExpensiveCapsule(prices,SIZE);
}
else if ( option == 3)
{
showAllCapsulesInStock(quantities, prices, SIZE, 10);
}
else if (option == 4){
findVP(prices, quantities, SIZE, BUDGET, SLEEVE);
}
else if(option == 5){
addMoreCapsules(quantities,SIZE);
}
else if(option == 9){
findC(prices, quantities, SIZE);
}
else
{
flag = true;
}
}
cout << "GoodBye!" << endl;
return 0;
}
This
return min, index;
doesn't do what you think it does. You obviously think it's going to return two values. But actually it just returns index.
This
mp, ind = findC(prices_copy, quantities_copy, SIZE);
doesn't do what you think it does. You obviously think it's going to assign the two returned values from findC to the variables mp and ind. But actually it's going to return the single value returned by findC to the variable ind and ignore mp.
If you want to know precisely what these constructs do then look up the comma operator, but I guess the moral of the story is that just because you can get some plausible looking code to compile it doesn't mean that it's going to do what you expected it to do.
So the real question is how to return two values from a function in C++. There are actually several possible approaches. Here's a question that reviews some of them, Returning multiple values from a C++ function.
The problem is:
A Class of 40 students has received their grades for 5 exams. Implement a function that calculates the worst average grade and display the the IDs of all students having the worst average grade.
I already calculated the average but do not know how to calculate the WORST average ( as in the lowest average of the 40 students) and displaying the ID numbers that have this number.
This is what I have written so far:
#include<iostream>
#include <iomanip>
using namespace std;
const int MAX_NUM = 6;
int x[MAX_NUM];
int y[5];
int main()
{
float avg;
float total = 0;
for (int i = 0; i < MAX_NUM; i++)
{
cout << "Enter an ID number: " << endl;
cin >> x[i];
cout << "Enter 5 grades: " << endl;
for (int j = 0; j < 5; j++)
{
cin >> y[j];
while (y[j]>100)
{
cout << "Please enter a valid grade that is less than a 100: " << endl;
cin >> y[j];
}
total += y[j];
}
avg = total / 5;
cout << "ID: " << x[i] << endl;
cout << "Average: "<< avg << endl;
}
Something like this:
Note: I have added some important statements!
#include<iostream>
#include <iomanip>
using namespace std;
const int MAX_NUM = 6;
int x[MAX_NUM];
int y[5];
float AVG[MAX_NUM];
int worstIDCount = 0;
int main()
{
float avg, min = 1001;
float total = 0;
for (int i = 0; i < MAX_NUM; i++)
{
avg = 0;
total = 0;
cout << "Enter an ID number: " << endl;
cin >> x[i];
cout << "Enter 5 grades: " << endl;
for (int j = 0; j < 5; j++)
{
cin >> y[j];
while (y[j]>100)
{
cout << "Please enter a valid grade that is less than a 100: " << endl;
cin >> y[j];
}
total += y[j];
}
avg = total / 5;
AVG[i] = avg;
if(avg < min)
min = avg;
cout << "ID: " << x[i] << endl;
cout << "Average: "<< avg << endl;
}
for(int i = 0; i < MAX_NUM; i++)
{
if(AVG[i] == min)
cout << "Student with WORST Average: ID" << x[i] << endl;
}
};
So you want to store these averages in a std::vector<float>, std::sort it and get the lowest. Then go back and find the students that have that average.
working example
#include <iostream>
#include <vector>
#include <functional> // mem_fn
#include <algorithm> // sort, upper_bound
#include <iterator> // ostream_iterator
struct Student_average {
int student_id;
float average;
};
bool compare_student_averages(Student_average const &lhs,
Student_average const &rhs) {
return lhs.average < rhs.average;
}
int main() {
std::vector<Student_average> averages;
// collect the data and populate the averages vector
// ...
sort(begin(averages), end(averages), compare_student_averages);
std::cout << "The worst average is: " << averages.front().average << '\n';
auto end_of_worst_student_averages =
upper_bound(begin(averages), end(averages), averages.front(),
compare_student_averages);
std::cout << "The IDs of the students with the worst averages are:\n";
transform(begin(averages), end_of_worst_student_averages,
std::ostream_iterator<int>(std::cout, "\n"),
std::mem_fn(&Student_average::student_id));
}
Here is a more C++ way of doing this using std::accumulate and std::min_element (I removed the check for anything > 100, for brevity):
#include <iostream>
#include <algorithm>
#include <numeric>
using namespace std;
const int MAX_NUM = 6;
int x[MAX_NUM];
int y[5];
int main()
{
float avg[5];
float total = 0;
for (int i = 0; i < MAX_NUM; i++)
{
cin >> x[i]; // ID
for (int j = 0; j < 5; ++j)
cin >> y[j]; // grades
// compute the average for this student
avg[i] = std::accumulate(y, y + 5, 0) / 5.0F;
cout << "ID: " << x[i] << endl;
cout << "Average: "<< avg[i] << endl;
}
// compute the worst average
float* worst_average = std::min_element(avg, avg + MAX_NUM);
// get the position in the array where the worst is found
int position = std::distance(avg, worst_average);
// output results
cout << "This person has the worst average: " << x[position]
<<". The average is " << *worst_average << "\n";
}
Note that the averages are stored in an array. The way the average is computed for each person is to use std::accumulate to add up the y array values, and then divide by 5.0.
Since we now have the averages in an aray, we want to find the smallest item in the array. To do that, min_element is used to get us the position of where the element is stored.
The trick here is that min_element returns a pointer to the smallest item, so we need calculate how far this pointer is located from the beginning of the avg array. To do this, the std::distance function is used. This now gives us the position of the smallest item.
The rest of the code just outputs the results.
As you can see, the only loops involved were the input loops. The calculation of the average and the worst average were done using accumulate and min_element, respectively.
Having trouble getting my code to run properly, first time I have ever used C++ and just trying to learn it for my knowledge, I am trying to get a 2d array with all zeros except in the final column. Inputs are stock = 100, strike = 100, time to maturity = 1, interest rate = 0.06, time steps = 3, upfactor = 1.1, downfactor = 0.9091. The end Array should look like {[0,0,0,133.10], [0,0,0,110], [0,0,0,90.91], [0,0,0,75.13]}, bot for some reason I keep getting values in the first column as well and I am stumped. Any advice?
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <math.h>
#include <cmath>
using namespace std;
int main(int nNumberofArgs, char*pszArgs[])
{
double st;
cout << " Enter Value of stock: ";
cin >> st;
double K;
cout << " Enter Value of strike price: ";
cin >> K;
double t;
cout << " Enter time of maturity: ";
cin >> t;
double r;
cout << " Enter Value of the interest rate: ";
cin >> r;
int N;
cout << " Enter Value of time steps: ";
cin >> N;
double u;
cout << " Enter value of up factor: ";
cin >> u;
double d;
cout << " Enter Value of down factor: ";
cin >> d;
double dt;
dt = t/N;
double p;
p = (exp(r*dt)-d)/(u-d);
// Initialise asset price at maturity time step N
double price[N][N];
for( int i = 0; i < N+1; i++)
{
for (int j = 0; j<N+1; j++)
{
price[i][j] = 0;
}
}
price[N][N] = st*pow(d,N);
cout << "price[N][N] is equal to: " << price[N][N] << endl;
double newN;
newN = N-1;
//cout << price[2][0] << endl;
for(int ii = newN; ii >=0; ii--)
{
price[ii][N] = (price[ii+1][N]) * (u/d);
}
//cout << price[2][0] << endl;
for( int i = 0; i <= N; i++)
{
for (int j = 0; j <=N; j++)
{
cout << price[i][j] << " ";
}
cout << endl;
}
system("PAUSE");
return 0;
}
The problem area is
for(int ii = newN; ii >=0; ii--)
{
price[ii][N] = (price[ii+1][N]) * (u/d);
}
and not sure exactly how to fix it. Any thoughts??
In C/C++ indexes are from 0
double price[N][N];
or
double price[10][10];
means that you have an array from 0..9 and 0..9
so
price[N][N] = st*pow(d,N);
is writing to a location outside the arrays as the maximum index is price[N-1][N-1]
and for that reason, loops in C/C++
for( int i = 0; i <= N; i++)
should be written as
for( int i = 0; i < N; i++)
since N is not included as a valid index value for the array.
Couple of issues with your program.
You have created a double dimensional array on stack with variable sized length (N).
If your array size is dynamic don't create it on stack, use new to allocate it on heap.
Also, as I see it you are accessing out-of-array entries. (Index greater than max array index)