Question

C++ please

1. Randomly assign integers in the range of 1-100 to a two-dimensional array. Write a program that finds the average value of the rows and the average value of the columns. Display the averages.

2. Create an array of randomly generated numbers in any range. Write a function that takes the array as an argument and returns an array that consists of only the even numbers in the original array. Use the function in a program.

3. Create an array of randomly generated numbers ranging from 1 to 100. Write a function that counts the number of array elements greater than or equal to a given value and returns the count. Use the function in a program.

4. Create an array of ten values using an initializer list. Write a function that swaps adjacent values, so that an array with the elements [1,2,3,4] becomes [2,1,4,3], but for 10 elements and not just 4. Display both the original array and the new array in your program.

5. Look up the definition of median and mode. Create an array of 100 randomly generated integers. Write a function that determines the median value of the array and a function that determines the mode of the array. Use the functions in a program.

Answer 1

Program :

1.

#include<iostream>

#include<cstdlib>

using namespace std;

int main() {

srand(time(NULL)); // time seed

int arr[5][5], i, j;

double sum;

cout << "\nThe 2D array is: ";

for (i = 0; i < 5; i++) {

cout << "\n";

for (j = 0; j < 5; j++) {

arr[i][j] = 1 + (rand() % 100); // generating random numbers for array

cout << arr[i][j] << " ";

}

}

for (i = 0; i < 5; i++) {

sum = 0;

for (j = 0; j < 5; j++)

sum += arr[i][j];

cout << "\nAverage of row - " << i + 1 << " is: " << sum / 5 << "\n"; // prints average of row

}

for (j = 0; j < 5; j++) {

sum = 0;

for (i = 0; i < 5; i++)

sum += arr[i][j];

cout << "\nAverage of column - " << j + 1 << " is: " << sum / 5 << "\n"; // prints average of column

}

return 0;

}

2.

#include<iostream>

#include<cstdlib>

using namespace std;

int* evenFind(int *a) {

int *eve = new int[10], j = 0;

for (int i = 0; i < 10; i++) {

if (a[i] % 2 == 0) {

eve[j] = a[i];

j++; // if array contains even numbers increase count by 1

}

}

return eve;

}

int main() {

srand(time(NULL));

int *arr = new int[10], i;

cout << "\nThe array is: ";

for (i = 0; i < 10; i++) {

arr[i] = 1 + (rand() % 100);

cout << arr[i] << " ";

}

arr = evenFind(arr);

cout << "\nThe array with even numbers is: ";

for (i = 0; i < 10; i++) {

if (arr[i] == 0)

continue;

else

cout << arr[i] << " "; // show the even elements in new array

}

cout << "\n";

}

3.

#include<iostream>

#include<cstdlib>

using namespace std;

int countFind(int *a, int v) {

int j = 0;

for (int i = 0; i < 10; i++) {

if (a[i] >= v)

j++; // increase count if array element is greater than value

}

return j;

}

int main() {

srand(time(NULL));

int *arr = new int[10], i, val, count;

cout << "\nThe array is: ";

for (i = 0; i < 10; i++) {

arr[i] = 1 + (rand() % 100);

cout << arr[i] << " ";

}

cout << "\nEnter the value: ";

cin >> val;

count = countFind(arr, val);

cout << "\nThe number of array elements greater than or equal to " << val << " is: " << count << "\n"; // show the count

}

4.

#include<iostream>

using namespace std;

int* swap(int *a) {

int temp;

for (int i = 0; i < 10; i += 2) {

temp = a[i];

a[i] = a[i + 1];

a[i + 1] = temp;

}

return a; // swapping adjascent numbers and returning the array

}

int main() {

int arr[10] = {10, 20, 30, 40, 50, 60, 70, 80, 90, 100}, *sw, i;

cout << "\nThe array is: ";

for (i = 0; i < 10; i++)

cout << arr[i] << " ";

sw = swap(arr);

cout << "\nThe array with swapped adjascent numbers is: ";

for (i = 0; i < 10; i++)

cout << sw[i] << " "; // displaying swapped elements of array

cout << "\n";

}

5.

#include<iostream>

#include<cstdlib>

using namespace std;

void findMedian(int *, int *, int, int *);

void findMode(int *a) {

int b[100], max = 0, i;

for (i = 0; i < 100; i++) {

if (a[i] > max)

max = a[i];

}

int n = max + 1, count[n];

for (i = 0; i < n; i++)

count[i] = 0;

for (i = 0; i < 100; i++)

count[a[i]]++;

int mode = 0, k = count[0];

for (i = 1; i < n; i++) {

if (count[i] > k) {

k = count[i]; // mode is the index with largest count

mode = i; // calculating mode

}

}

cout << "\nThe mode of the array is:" << mode << "\n";

findMedian(a, count, n, b);

}

void findMedian(int *a, int *count, int n, int *b) {

for (int i = 1; i < n; i++)

count[i] = count[i] + count[i - 1]; // updating count with summing

for (int i = 0; i < 100; i++) {

b[count[a[i]] - 1] = a[i];

count[a[i]]--; // sorting count array to calculate median

}

float median = (b[(n - 1) / 2] + b[(n / 2)]) / 2.0; // calculating mean for even array size 100

cout << "\nThe median of the array is: " << median << "\n";

}

int main() {

srand(time(NULL));

int *arr = new int[100], *m, i;

cout << "\nThe array is: ";

for (i = 0; i < 100; i++) {

arr[i] = 1 + (rand() % 100);

cout << arr[i] << " ";

}

findMode(arr);

}

Output :