Exercise 7.4 (Completed)

1. (Practice) Write specification statements for the following:
a. An array of integers with 6 rows and 10 columns

const int NUMROWS = 6;
const int NUMCOLS = 10;
int val[NUMROWS][NUMCOLS];
      
b. An array of integers with 2 rows and 5 columns

const int NUMROWS = 2;
const int NUMCOLS = 5;
int val[NUMROWS][NUMCOLS];
      
c. An array of characters with 7 rows and 12 columns

const int NUMROWS = 7;
const int NUMCOLS = 12;
char val[NUMROWS][NUMCOLS];
      
d. An array of characters with 15 rows and 7 columns

const int NUMROWS = 15;
const int NUMCOLS = 7;
char val[NUMROWS][NUMCOLS];

e. An array of double-precision numbers with 10 rows and 25 columns

const int NUMROWS = 10;

const int NUMCOLS =7;
char val[NUMROWS][NUMCOLS];

f. An array of double-precision numbers with 16 rows and 8 columns

const int NUMROWS = 16;
const int NUMCOLS = 8;
char val[NUMROWS][NUMCOLS];

2. (Desk check) Determine the output produced by the following program:
#include <iostream>
using namespace std;
int main()
{
  int i, j, val[3][4] = {8,16,9,52,3,15,27,6,14,25,2,10};
  for (i = 0; i < 3; i++)
    for (j = 0; j < 4; j++)
      cout << val[i][j] << “ “;
  return 0;
}

The output is as follows:
8   16   9   52   3   15   27   6   14   25   2   10

3. (Program) a. Write, compile, and run a C++ program that adds the values of all elements in
the val array used in Exercise 2 and displays the total.

#include <iostream>
using namespace std;

int main(){
	int i, j, val[3][4] = { 8, 16, 9, 52, 3, 15, 27, 6, 14, 25, 2, 10 };
	int total = 0;
	for (i = 0; i < 3; i++){
		for (j = 0; j < 4; j++){
		cout << val[i][j] << " " << endl;
		total = total + val[i][j];
		
	}
}
	cout << "The total is " << total << endl;
		system("PAUSE");
		return 0;
	}


b. Modify the program written for Exercise 3a to display the total of each row separately.

#include <iostream>
using namespace std;

int main(){
	int i, j, val[3][4] = { 8, 16, 9, 52, 3, 15, 27, 6, 14, 25, 2, 10 };
	int total = 0;
	for (i = 0; i < 3; i++){
		for (j = 0; j < 4; j++){
			total = total + val[i][j];
		cout << val[i][j] << " " <<"The new total is  " << total << endl;
		
		
	}

}
	
		system("PAUSE");
		return 0;
	}

4. (Program) Write, compile, and run a C++ program that adds equivalent elements of the twodimensional
arrays named first and second. Both arrays should have two rows and three columns.
For example, element [1][2] of the resulting array should be the sum of first[1][2]
and second[1][2]. The first and second arrays should be initialized as follows:
    first             second
16   18   23        24   52   77
54   91   11        16   19   59

#include <iostream>
using namespace std;

int main(){
	int i, j, first[2][3] = { 16,18,23,54,91,11 };
	int second[2][3] = { 24, 52, 77, 16, 19, 59 };
	int total = 0;
	for (i = 0; i < 2; i++){
		for (j = 0; j < 3; j++){
			total = second[i][j] + first[i][j];
			cout << total << endl;
		
		
	}
}
	
		system("PAUSE");

5. (Program) a. Write, compile, and run a C++ program that finds and displays the maximum value
in a two-dimensional array of integers. The array should be declared as a 4-by-5 array of integers
and initialized with the data 16, 22, 99, 4, 18, -258, 4, 101, 5, 98, 105, 6, 15, 2, 45, 33, 88, 72, 16, and 3.

#include <iostream>
using namespace std;


int main(){
		   double arr[4][5] = { 16, 22, 99, 4, 18,
			                -258, 4, 101, 5, 98,
			                 105, 6, 15, 2, 45, 
					 33, 88, 72, 16, 3 };
	   
		   for (int i = 0; i < 4; i++){
			   for (int j = 0; j < 4; j++){
				   if (arr[i][j] > arr[0][0]){
					   arr[0][0] = arr[i][j];
					  
				   }
			   }
		   }
	
		   cout << arr[0][0] << endl;
		system("PAUSE");
		return 0;
	}

b. Modify the program written in Exercise 5a so that it also displays the maximum value’s row
and column subscript values.

#include <iostream>
using namespace std;


int main(){
		   double arr[4][5] = { 16, 22, 99, 4, 18,
			                  -258, 4, 101, 5, 98,
			                   105, 6, 15, 2, 45, 
					     	   33, 88, 72, 16, 3 };
		   int a = 0; int b = 0;
	   
		   for (int i = 0; i < 4; i++){
			   for (int j = 0; j < 4; j++){
				   if (arr[i][j] > arr[0][0]){
					   arr[0][0] = arr[i][j];
					   a = i;
					   b = j;
				   }
			   }
		   }
	
		   cout << arr[0][0] << setw(10) << a << setw(10)<< b << endl;
		system("PAUSE");
		return 0;
	}

6. (Program) Write, compile, and run a C++ program that selects the values in a 4-by-5 array of
positive integers in increasing order and stores the selected values in a one-dimensional array
named sort. Use the data given in Exercise 5a to initialize the two-dimensional array.

#include <iostream>
using namespace std;

int main(int argc, char **argv) {
	const int SIZE = 20;
	int arr[4][5] = { 16, 22, 99, 4, 18,
		             -258, 4, 101, 5, 98,
		              105, 6, 15, 2, 45,
		              33, 88, 72, 16, 3 };
	int *sort = (int*)arr;
	int temp;

	std::sort(sort, sort + SIZE);


	for (int k = 0; k<20; k++) {
		cout << sort[k] <<endl;
		//printf("arr[%d] = %2d\n", k, sort[k]);
	}

		system("PAUSE");
		return 0;
	}

7. (Program) a. A professor has constructed a 3-by-5 two-dimensional array of grades. This array
contains the test grades of students in the professor’s advanced compiler design class. Write,
compile, and run a C++ program that reads 15 array values and then determines the total number
of grades in these ranges: less than 60, greater than or equal to 60 and less than 70, greater
than or equal to 70 and less than 80, greater than or equal to 80 and less than 90, and greater
than or equal to 90.

#include <iostream>
using namespace std;

int main() {
	const int SIZE = 15;
	int arr[3][5];
	int *arr2 = (int*)arr;
	int count = 0, count2 = 0, count3 = 0, count4 = 0, count5 = 0;
	
	for(int j =0; int j=15; j++){
	for(int k =0; int k = 15; j++){
	cin << arr[j][k]<< endl;
	}
	}
	for (int i = 0; i < 15; i++){
		if (arr2[i] < 60){
			count++;
		}
		else if (arr2[i] >= 60 && arr2[i] <= 70){
			count2++;
		}
		else if (arr2[i] >= 70 && arr2[i] <= 80){
			count3++;
		}
		else if (arr2[i] >= 80 && arr2[i] <= 90){
			count4++;
		}
		else if (arr2[i] >= 90){
			count5++;
		}
	}	cout << "Less than 60 " << count << endl;
	cout << "Greater than or equal to 60 and less than 70 " << count2 << endl;
	cout << "Greater than or equal to 70 and less than 80 " << count3 << endl;
	cout << "Greater than or equal to 80 and less than 90 " << count4 << endl;
	cout << "Greater than or equal to 90 " << count5 << endl;

		system("PAUSE");
		return 0;
	}

b. Entering 15 grades each time you run the program written for Exercise 7a is cumbersome.
What method can be used for initializing the array during the testing phase?

int arr[3][5] = { 100, 22, 99,40,90, 89,78, 50, 98,100, 61, 94,95, 67 ,100};

c. How might the program you wrote for Exercise 7a be modified to include the case of no
grade being input? That is, what grade could be used to indicate an invalid grade, and how
would your program have to be modified to exclude counting an invalid grade?

if(arr2[i] == NULL){cin.ignore}
//if the input is invalid than the value that was entered can be ignored.

8. (Program) a. Create a two-dimensional list of integer part numbers and quantities of each
part in stock, and write a function that displays data in the array in decreasing quantity order.
No more than 100 different parts are being tracked. Test your program with the following data:
Part No. Quantity
1001     62
949      85
1050     33
867      125
346      59
1025     105
 
#include <iostream>
using namespace std;

int main() {
	int a[][6] = {
		{   62, 85,  33,125, 59,105 },   // Quantity   
		{ 1001,949,1050,867,346,1025 }   // Part No.   
	};
	int i, j, k, temp, temp1;

	//Bubble sorting is applieed on one first row while the other row is swapped

	for (j = 1; j<6; j++)
	{
		for (i = 0; i<5; i++)
		{
			if (a[0][i]<a[0][i + 1])
			{
				temp = a[0][i];
				a[0][i] = a[0][i + 1];
				a[0][i + 1] = temp;

				temp1 = a[1][i];
				a[1][i] = a[1][i + 1];
				a[1][i + 1] = temp1;
			}
		}
	}

	printf("\n\nArray after sorting:\n");
	for (i = 0; i <2; i++)
	{
		
		for (j = 0; j<6; j++)
		{
			printf("%d\t", a[i][j]);        //printing sorted array
		}
		printf("\n");
	}
	


		system("PAUSE");
		return 0;
	}

b. Modify the function written in Exercise 8a to display the data in part number order.

#include <iostream>
using namespace std;

int main() {
	int a[][6] = {
		{ 1001, 949, 1050, 867, 346, 1025 },   // Part No.   
		{ 62, 85, 33, 125, 59, 105 }   // Quantity  
	};
	int i, j, k, temp, temp1;

	//Bubble sorting is applieed on one first row while the other row is swapped

	for (j = 1; j<6; j++)
	{
		for (i = 0; i<5; i++)
		{
			if (a[0][i]<a[0][i + 1])
			{
				temp = a[0][i];
				a[0][i] = a[0][i + 1];
				a[0][i + 1] = temp;

				temp1 = a[1][i];
				a[1][i] = a[1][i + 1];
				a[1][i + 1] = temp1;
			}
		}
	}

	printf("\n\nArray after sorting:\n");
	for (i = 0; i <2; i++)
	{
		
		for (j = 0; j<6; j++)
		{
			printf("%d\t", a[i][j]);        //printing sorted array
		}
		printf("\n");
	}
	


		system("PAUSE");
		return 0;
	}

9. (Program) a. Your professor has asked you to write a C++ program that determines grades for
five students at the end of the semester. For each student, identified by an integer number, four
exam grades must be kept, and two final grade averages must be computed. The first grade
average is simply the average of all four grades. The second grade average is computed by
weighting the four grades as follows: The first grade gets a weight of 0.2, the second grade gets
a weight of 0.3, the third grade gets a weight of 0.3, and the fourth grade gets a weight of 0.2.
That is, the final grade is computed as follows:
0.2 * grade1 0.3 * grade2 0.3 * grade3 0.2 * grade4
Using this information, construct a 5-by-6 two-dimensional array, in which the first column is
used for the student number, the next four columns for the grades, and the last two columns
for the computed final grades. The program’s output should be a display of the data in the
completed array. For testing purposes, the professor has provided the following data:
Student Grade 1 Grade2 Grade 3 Grade 4
1       100     100    100     100
2       100     0      100     0
3       82      94      73     86
4       64      74      84     94
5       94      84      74     64
Regular Final Grade:
Weight Final Grade:

#include <algorithm>
#include <iostream>
using namespace std;

int main() {



	double grade[5][6] = { { 1, 100, 100, 100, 100 },
	{ 2, 100, 0, 100, 0 },
	{ 3, 82, 94, 73, 86 },
	{ 4, 64, 74, 84, 94 },
	{ 5, 94, 84, 74, 64 },
	};
	for (int i = 0; i < 5; i++){
		for (int j = 0; j < 6; j++){
			 grade[i][6] = (grade[i][1] * .2) + (grade[i][2] * .3) + (grade[i][2] * .3) + (grade[i][4] * .2);
			 grade[i][5] = (grade[i][1] + grade[i][2] + grade[i][3] + grade[i][4]) / 4;



		}
	}
	for (int i = 0; i < 5; i++){
		cout << "This is the regualar average for Student " << (i + 1) << endl;
		cout << grade[i][5] << endl;
	}
	for (int k = 0; k < 5; k++){
	cout << "This is the weighed final grade for Student " << (k+1)<< endl;
	cout << grade[k][6] << endl;
}

		system("PAUSE");
		return 0;
	}

b. What modifications would you need to make to your program so that it can handle 60 students
rather than 5?

Increasing the range of the variable i would also increase the number of students that can be handled.
Ex. for(int i = 0; i < 60; i++)

c. Modify the program written for Exercise 9a by adding an eighth column to the array. The
grade in the eighth column should be calculated by computing the average of the top three
grades only.

#include <iostream>
using namespace std;

int main() {


	int total = 0,lowest=0;
	int grade[5][7] = { { 1, 100, 100, 100, 100 },
	{ 2, 100, 0, 100, 0 },
	{ 3, 82, 94, 73, 86 },
	{ 4, 64, 74, 84, 94 },
	{ 5, 94, 84, 74, 64 },
	};
	for (int i = 0; i < 5; i++){
		for (int j = 0; j < 7; j++){
			 grade[i][6] = (grade[i][1] * .2) + (grade[i][2] * .3) + (grade[i][2] * .3) + (grade[i][4] * .2);
			 grade[i][5] = (grade[i][1] + grade[i][2] + grade[i][3] + grade[i][4]) / 4;
			 
			
			 
			 total = grade[i][1] + grade[i][2] + grade[i][3] + grade[i][4];
			 if (grade[i][7] <= grade[i][lowest])
				 lowest = j;
			 total -= grade[lowest][7];
			 grade[i][7] = (total / 3);


		}
	}

	
	
	for (int i = 0; i < 5; i++){
		cout << "This is the regualar average for Student " << (i + 1) << endl;
		cout << grade[i][5] << endl;
	}
	for (int k = 0; k < 5; k++){
	cout << "This is the weighed final grade for Student " << (k+1)<< endl;
	cout << grade[k][6] << endl;
}
	for (int m = 0; m < 5; m++){
		cout << "The best grades final grade solution of student " << (m + 1) << endl;
		cout << grade[m][7] << endl;
	}

		system("PAUSE");
		return 0;
	}

10. (Program) The answers to a true-false test are as follows: T T F F T. Given a two-dimensional
answer array, in which each row corresponds to the answers provided on one test, write a function
that accepts the two-dimensional array and number of tests as parameters and returns a
one-dimensional array containing the grades for each test. (Each question is worth 5 points so
that the maximum possible grade is 25.) Test your function with the following data:
Test 1: T F T T T
Test 2: T T T T T
Test 3: T T F F T
Test 4: F T F F F
Test 5: F F F F F
Test 6: T T F T F

#include <iostream>
using namespace std;

int *getMarks(const char answers[][5], size_t ntests);

int main()
{
	char tests[6][5] = {
		{ 'T', 'F', 'T', 'T', 'T' },
		{ 'T', 'T', 'T', 'T', 'T' },
		{ 'T', 'T', 'F', 'F', 'T' },
		{ 'F', 'T', 'F', 'F', 'F' },
		{ 'F', 'F', 'F', 'F', 'F' },
		{ 'T', 'T', 'F', 'T', 'F' },
	};

	int *marks = getMarks(tests, 6);
	for (size_t j = 0; j < 6; j++)
		std::cout << marks[j] << " ";
	system("PAUSE");
	return 0;
}

int *getMarks(const char answers[][5], size_t ntests)
{
	const char answer[5] = { 'T', 'T', 'F', 'F', 'T' };
	int *marks = new int[ntests]();
	const int mark = 5;

	for (size_t j = 0; j < ntests; j++)
		for (size_t i = 0; i < 5; i++)
			if (answers[j][i] == answer[i])
				marks[j] += mark;

	return marks;
}

11. (Modify) Modify the function you wrote for Exercise 10 so that each test is stored in column
order rather than row order.

#include <iostream>
using namespace std;

int *getMarks(const char answers[][5], size_t ntests);

int main()
{
	char tests[6][5] = {
		{ 'T', 'F', 'T', 'T', 'T' },
		{ 'T', 'T', 'T', 'T', 'T' },
		{ 'T', 'T', 'F', 'F', 'T' },
		{ 'F', 'T', 'F', 'F', 'F' },
		{ 'F', 'F', 'F', 'F', 'F' },
		{ 'T', 'T', 'F', 'T', 'F' },
	};

	int *marks = getMarks(tests, 6);
	for (size_t j = 0; j < 6; j++)
		std::cout <<"The score of Test "<< j+1 <<" is "<< marks[j] << " "<< endl;
	system("PAUSE");
	return 0;
}

int *getMarks(const char answers[][5], size_t ntests)
{
	const char answer[5] = { 'T', 'T', 'F', 'F', 'T' };
	int *marks = new int[ntests]();
	const int mark = 5;

	for (size_t j = 0; j < ntests; j++)
		for (size_t i = 0; i < 5; i++)
			if (answers[j][i] == answer[i])
				marks[j] += mark;

	return marks;
}

12. (Program) A three-dimensional weather array for the months July and August 2011 has columns
labeled by the month numbers 7 and 8. In each column, there are rows numbered 1
through 31, representing the days, and for each day, there are two ranks labeled H and L,
representing the day’s high and low temperatures. Use this information to write a C++ program
that assigns the high and low temperatures for each element of the arrays. Then allow
the user to request the following:
• Any day’s high and low temperatures
• Average high and low temperatures for a given month
• Month and day with the highest temperature
• Month and day with the lowest temperature

#include <algorithm>
#include <iostream>
using namespace std;

int main(){

	const int ROW = 31;
	const int COLUMN = 2;
	const int RANK = 2;
	
	int arr[ROW][COLUMN][RANK];
	int averageJuly, averageAugust, total1, total2,highJuly,lowJuly,highAug,lowAug;
	int dayhighAug, daylowAug,dayhighJuly,daylowJuly;
		char month;
		int i;
	for (int i = 0; i < 31; i++){
		for (int j = 0; j < 2;j++){
			for (int k = 0; k < 2; k++){
				cout << "Enter high temeratures of the month" << j+7<<" for " << i+1 << "day" << endl;
				std::cin >> arr[i][j][0];
				cout << "Enter low temeratures of the month" << j+7<< " for " << i+1 << "day" << endl;
				std::cin >> arr[i][j][1];
				
					total1 = +arr[i][j][0];
					total2 = +arr[i][j][1];
					averageJuly = total1 / 31;
					averageAugust = total2 / 31;

						if (arr[i][0][0] > arr[0][0][0])
						{
							arr[0][0][0] = arr[i][0][1];
							highJuly = arr[0][0][0];
						}

						if (arr[i][0][0] < arr[0][0][0])
						{
							arr[0][0][0] = arr[i][0][1];
							lowJuly = arr[0][0][0];
						}
						if (arr[i][1][1] > arr[0][0][0])
						{
							arr[0][0][0] = arr[i][1][1];
							highAug = arr[0][0][0];
						}

						if (arr[i][1][1] < arr[0][0][0])
						{
							arr[0][0][0] = arr[i][1][1];
							lowAug = arr[0][0][0];
						}

						dayhighAug = arr[i][0][0];
						daylowAug = arr[i][0][1];
						dayhighJuly = arr[i][1][0];
						daylowJuly = arr[i][1][1];
			}
		}
	}
	cout << "Any day's high and low temperatures" << endl;
	std::cin >> month;
	if (month == 'A'){
		cout << "Enter day" << endl;
		std::cin >> i;
		cout << dayhighAug << endl;
		cout << daylowAug << endl;
	}
	else if (month == 'J'){
		cout << "Enter day" << endl;
		std::cin >> i;
		cout << dayhighJuly << endl;
		cout << daylowJuly << endl;
	}
	 
	cout << "Average high and low temperatures for a given month" << endl;
	std::cin >> month;
	if (month == 'A'){
		cout << averageAugust << endl;
	}
	else if (month == 'J'){
		cout << averageJuly << endl;
	}
	cout << "Month and day with the highest temperature" << endl;
	std::cin >> month;
	if (month == 'A'){
		cout << highAug << endl;
	}
	else if (month == 'J'){
		cout << highJuly << endl;
	}
	cout << "Month and day with the lowest teperature" << endl;
std:: cin >> month;
	if (month == 'A'){
		cout << lowAug << endl;
	}
	else if (month == 'J'){
		cout << lowJuly << endl;
	}
	system("PAUSE");
	return 0;
}