Question

C Programming

write two functions, similar to what you see in the sample program. The first will ask the user to enter some information (I have included the type in parentheses)

• First Name (char[])
• Last Name (char[])
• Age (int)
• Height in Inches (double)
• Weight in Pounds (double)

You will use pass-by-reference to modify the values of the arguments passed in from the main(). Remember that arrays require no special notation, as they are passed by reference automatically, but the other three will need to be declared as pointers of the appropriate type.

Note: Remember that the address operator & and indirection operator * are complements of each other, and cancel each other out. This will be an important distinction in determining how to write the scanf statements for age, height, and weight.

The second function will accept the five values determined by the previous function, and display the results to the screen in a formatted style, perhaps similar to what you see in the sample output below. Because we are not changing any values in this second function, you will not need to use pointer parameters here.

Your main will be relatively short this time. You will have the variable declarations for storing your five pieces of information, a call to your first function to get the values, and a call to your second function to display them. (To clear the screen in Windows, use a system(“cls”); statement between the two function calls. Clearing the screen is not required for full credit on the lab).

*SAMPLE PROGRAM*

#include 
#include 
#include 

///////// SYMBOLIC CONSTANTS /////////

#define SIZE 1000                       // There is an upper limit on this SIZE, based on the max amount of memory that
                                                        // the program can allocate. If you try to increase it, the program may crash.

#define RANGE 25000                     // A symbolic constant used to determine the range of random numbers generated.




//////// FUNCTION PROTOTYPES /////////

void findMinMax(int valueArr[], int size, int *min, int *max, long *sum, double *avg);
        // Function will determine the min and max values in the array, as well as the average and sum.
        // It returns these values by using the pointer parameters to change the value of the argument passed from main.

void displayStats(int min, int max, long sum, double avg);
        // Function will print out the resulting information in a nicely formatted form.
        // As we are not changing the values here, we do not pass these values by reference this time.

//////// FUNCTION DEFINITIONS ////////

int main()
{
        int randoms[SIZE];              // Array of which will hold SIZE randomly generated ints. This will be our data set                                             
        int index;                              // A loop control variable for our for loops.
        int min, max;                   // These variables (plus sum and average below) will be passed into the findMinMax function by reference.
        long sum;
        double average;                 // Passing them by reference will allow us to change their values here in the main.

        // First, we seed the random number generator. We only want to do this once, so we leave it outside of the loop.
        srand((unsigned)time(NULL));

        // Next, we use a for loop to initialize all SIZE elemements of our array.
        for (index = 0; index < SIZE; index++)
        {
                randoms[index] = rand() % RANGE + 1;
        }

        findMinMax(randoms, SIZE, &min, &max, &sum, &average);  // We call findMinMax to calculate the min, max, sum, and average.
                                                                                                                        // The & address operator before the final four arguments ensures
                                                                                                                        // that they are passed by reference.

        displayStats(min, max, sum, average);

        printf("Press Enter to continue...");
        getchar();
        return 0;
}



void findMinMax(int valueArr[], int size, int *min, int *max, long *sum, double *avg)
{
        int i;  // Our usual loop control variable, which will serve as the array subscript index.

        // Let's initialize any variables we need to initialize.
        // We dereference the pointers using * so we can changes the values they point to, not the address.
        *sum = 0;                       // Sum is an accumulator, so we must start counting from 0.
        *min = valueArr[0];     // To find the min, we will start by assuming the first number is the smallest.
        *max = valueArr[0]; // Like with min, we will assume that the first number is the largest for max.


        for(i = 0; i < size; i++)
        {
                // First, lets add the value in the array at each position to the sum;
                *sum += valueArr[i];

                // Next, we'll use an if statement to update the min, if needed.
                if(valueArr[i] < *min)               
                        *min = valueArr[i];

                // Now we'll do the same thing for max.
                if(valueArr[i] > *max)
                        *max = valueArr[i];
        }

        // Now that we've looped through all of the elements in the array and have the sum total, we can find average.
        // Because we are working with integers, we will need to cast sum to a double so we can get a floating point result.
        *avg = (double)*sum / size;

        // Our function ends at this point. We've calculated all of our values, and have nothing to return because of the void type.
}


void displayStats(int min, int max, long sum, double avg)
{
        printf("Array Summary Statistics:\n");
        printf("-------------------------\n");
        printf("|                       |\n");
        printf("| Minimum Value: %-6d |\n", min);
        printf("| Maximum Value: %-6d |\n", max);
        printf("| Sum: %-17d|\n", sum); 
        printf("| Average: %-13.2f|\n", avg);
        printf("-------------------------\n");
}

Answer 1

Please find the c program using pass by reference to read the values of firstname, lastname,age, height, weight.

Program:

#include <stdio.h>

void read(char *namefirst,char *namelast, int *age, double *height, double *weight)
{
printf("Enter the first name: ");
gets(namefirst);
  
printf("Enter the last name: ");
gets(namelast);
  
printf("Enter the age: ");
scanf("%d", age);
  
printf("Enter the height: ");
scanf("%lf", height);
  
printf("Enter the weight: ");
scanf("%lf", weight);
  
printf("\n\n");
}

void printdetails(char *namefirst,char *namelast, int age, double height, double weight)
{
printf(" Details of a person:\n");
printf("-------------------------------\n");

printf("|First name: %-17s|\n", namefirst);
  
  
printf("|Last name: %-17s|\n", namelast);
  
  
printf("|Age: %-17d|\n", age);
  
printf("|Height: %-10.2lf inches|\n", height);
  
  
printf("|Weight: %-10.2lf pounds|\n", weight);

printf("-------------------------------\n");
}

int main()
{
char namefirst[50];
char namelast[50];
int age =0;
double height =0, weight =0;
  
read(namefirst, namelast, &age, &height, &weight);
  
printdetails(namefirst, namelast, age, height,weight);

return 0;
}

Output:

Enter the first name: Lebron
Enter the last name: James
Enter the age: 34
Enter the height: 6.8
Enter the weight: 234

Details of a person:
-------------------------------
|First name: Lebron |
|Last name: James |
|Age: 34 |
|Height: 6.80 inches|
|Weight: 234.00 pounds|
-------------------------------

Screen Shot:

nter the fir t name: Lebron nter the la t name : James ter the age: 34 Enter the height: 6.8 nter the weight: 234 Details of a person: First name: Lebron ILast name: James Age: Height: 6.80 Weight: 234.00ounds 34 inches