As an aid, feel free to use the following questions to help you generate content for your entries:

• What action or concept of significance, as related to the course, did you experience on this date?

In the first days of class concepts of significance that I have taken away from said learning are:

svn add and svn commit actions.

pointers, using pointers in C programming code.

integers, chars, using integers and chars as pointers, using integers and chars in C programming code.

include action, using include actions in C programming to use libraries.

• Why was this significant?

The svn commands are great for saving information to your directories and committing changes.

The pointers are used to have something exist in memory but no be contained in a certain place.

The integers and chars can be used to declare variables.

The include action is used to reference pre-existing libraries contained in the C programming language.

• What concepts are you dealing with that may not make perfect sense?

Something that does not make perfect sense to me at this point in the class so far is the “%u\n” “%d\n” portions of code.

• What challenges are you facing with respect to the course?

My challenge with a C programming course is that I have no previous experience with a programming language, a lot of new information to grasp.

With this in class example we used pointers, malloc, a while loop, if condition, else and else if condition, srand, time, NULL,

malloc was a call for an allocation of memory.

While loop with conditions was our implementation to keep the program running for more than one instance.

srand was our pseudo random number generator.

time was our value system of numbers that srand used to return random numbers? I think.

If I remember correctly when you NULL something you are acknowledging that it exists without physically or logically assigning it a specific value, out it's were the integer pointers input and pick.

We also talked about how it was difficult for a computer to be random without eventually becoming predictable in some way, due to the facts of the way a computer operates always following instructions, and not having the distinct ability to make a decision on it's own accord.

#include<stdio.h>

#include<stdlib.h>

int main()

{

int *input, *pick; input=pick=NULL;
input=(int *)malloc(sizeof(int)*1);
pick=(int *)malloc(sizeof(int)*1);
*input=0;
*pick=0;
while(*pick !=-1)
{
	srand(time(NULL));
	*pick=rand()%99+1;
	printf("Guess the computer's pick: ");
	scanf("%d", input);
	if(*input==*pick)
	{
		printf("Congratulations you have won\n");
	}
	else if(*input > *pick)
	{
		printf("Your guess was high\n");
	}
	else
	{
		printf("Your guess was low\n");
	}
	printf("Computer had %d\n", *pick);
	printf("0 to play again, -1 to quit\n");
	scanf("%d", pick);
}
return(0);

}

With this class example we used new C/C++ components argc and argv

argc in C/C++ is the argument count within a programs pseudo code, we used the argument counter in this program to say that if the argument count was less than 2 the program would print a string message to the user telling them that need more arguments and how many arguments they actually provided.

argv is an abbreviation for an argument vector, we used argv as a double pointer character, that is really the best I can explain what this is doing at this point.

#include<stdio.h>
#include<stdlib.h>
int main(int argc, char **argv)
 
{
	unsigned char i;
	if(argc<2)
	{
		printf("%8s must be run with 1 or more arguments, you only provided %hhu\n",(argc-1));
		exit(1);
	}
	printf("You ran this program with %hhu arguments, they are:\n",(argc-1));
	for(i=1;i<argc;i++)
	{
		printf("argv[%hhu]: %s\n",i,*(argv+i));
	}
	return(0);
}

I am adding all of the coded examples that we have done in class so far as my 4th opus entry. Probably add some textual content about what each program was focusing on once I get the format of the entry all setup with the all the examples included.

Example 1

#include
<stdio.h>
int main()
 
{
	printf("an int is %u bytes\n", sizeof(int));
	return(0);
}

Example 2

#include
<stdio.h>
int main()
{
	int a;
	a=0;
	printf("a contains %u\n", a);
	printf("a's address is 0x%x\n", &a);
	return(0);
}

Addition to var2.c
#include<stdio.h>
int main()
{
	int a=0;
	int *b;
	b=&a;
	*b=12;
	printf("a contains %u\n", a);
	printf("a's address is 0x%x\n", &a);
	printf("b contains %u\n, *b);
	printf("b points to 0x%x\n, b);
	printf("b's address is 0x%x\n",&b);
	return(0);
}	

Example 3

#include<stdio.h>
int main()
{
	int v=17;  //setting the integer v equal to the number 17
	int *p1=NULL; //setting the pointer p1 to NULL, NULL is allowing p1 to exist without 				assigning an exact value
	printf(“v is %u\n”, v);  //having the computer display or “print out” the value of v
	p1=&v;
	printf(“*p1 is %u\n”, *p1);
	*p1=53;
	printf(“v is %u\n”, v);
	printf(“*p1 is %u\n”, *p1);
	v=7;
	printf(“v is %u\n”, v);
	printf(“*p1 is %u\n”, *p1);
	return(0);
}

Example 4

#include<stdio.h>
int main()
{
	int num=0;
	printf(“Please enter an integer value: “);
	scanf(“%d”,&num);
	printf(“You just input %d\n”,num);
	if((num % 2) == 0)
	{
		printf(“It is even.\n”);
	}
	else
	{
		printf(“It is odd.\n”);
	}
	return(0);
}

Example 5

#include<stdio.h>
#include<stdlib.h>
int main()
{
	int *p1,*p2,**p4;
	p1=(int *)malloc(sizeof(int)*1);
	*p1=26;
	printf("*p1 is %u\n",*p1);
	p2=p1;
	p4=&p1;
	printf("**p4 is %u\n",**p4);
	printf("*p2 is %u\n",*p2);
	*p2=61;
	printf("*p1 is %u\n",*p1);
	printf("**p4 is %u\n",**p4);
	printf("*p2 is %u\n",*p2);
	**p4=16384;
	printf("*p1 is %u\n",*p1);
	printf("**p4 is %u\n",**p4);
	printf("*p2 is %u\n",*p2);
	return(0);
}

Example 6

#include<stdio.h>
#include<stdlib.h>
int main()
{
	int *input, *pick; input=pick=NULL;
	input=(int *)malloc(sizeof(int)*1);
	pick=(int *)malloc(sizeof(int)*1);
	*input=0;
	*pick=0;
	while(*pick !=-1)
	{
		srand(time(NULL));
		*pick=rand()%99+1;
		printf("Guess the computer's pick: ");
		scanf("%d", input);
		if(*input==*pick)
		{
			printf("Congratulations you have won\n");
		}
		else if(*input > *pick)
		{
			printf("Your guess was high\n");
		}
		else
		{
			printf("Your guess was low\n");
		}
		printf("Computer had %d\n", *pick);
		printf("0 to play again, -1 to quit\n");
		scanf("%d", pick);
	}
	return(0);
}

Example 7

#include<stdio.h>
#include<stdlib.h>
 
int main()
{
        char *value,i;
        value=(char *)malloc(sizeof(char)*4);
        *(value+0)=0;
        *(value+1)=1;
        fprintf(stdout, "please enter a value (-128-+127):");
        fscanf(stdin,"%hhd",&i);
        *(value+2)=i;
        *(value+3)=(2*i)+3;
        for(i=3;i>=0;i--) //(i=0;i<=3;i++)
        {
                printf("%hhd\n",*(value+i));
        }
        return(0);
}

Example Sample

#include<stdio.h>
#include<stdlib.h>
int main(int argc, char **argv) //parameters are in the ( ), first parameter of main must be an integer
{
        unsigned char i;
 
        if(argc<2)
        {
                printf("%8s must be run with 1 or\
 more arguments, you only provided %hhu\n",*(argv+0),(argc-1));
                exit(1); // \ followed by enter allows you to continue code on new line
        }
        printf("You ran this program with %hhu arguments, they are:\n",(argc-1));
        for(i=1;i<argc;i++)
        {
                printf("argv[%hhu]: %s\n",i,*(argv+i));
        }
        return(0);
}

Example FileFun

#include<stdio.h>
#include<stdlib.h>

int main()
{
        FILE *in,*out;
        char value=0;
        in=fopen("file.txt","r");
        out=fopen("out.txt","w");
        if(in==NULL)
        {
                printf("ERROR!\n");
                exit(1);
        }
        fscanf(in,"%hhd",&value);
        while(value != -1)
        {
                value*=2;
                fprintf(out,"%hhd\n",value);
                fscanf(in,"%hhd",&value);
        }
        fclose(in);
        fclose(out);
        return(0);
}

Project 0 or as I like to call it range.c

#include <stdio.h>
#include <math.h>
int main()
{
    // Variables
    unsigned long long int quantity = 0;
    unsigned char uc = 0;
    signed char sc = 0;
    unsigned short int usi = 0;
    signed short int ssi = 0;
    unsigned int ui = 0;
    signed int si = 0;
    unsigned long int uli = 0;
    signed long int sli = 0;
    unsigned long long int ulli = 0;
    signed long long int slli = 0;
    // Display information for unsigned char data type
    printf("An unsigned char is %d bytes\n", sizeof(uc));
    printf("The range of an unsigned char is %hhu to %hhu\n", uc, (uc-1));
    quantity = (unsigned char)(uc-1) + 1;    // What does this line do?
    printf("An unsigned char can store %llu unique values\n\n", quantity);
    // Display information for signed char data type
    printf("A signed char is %d bytes\n", sizeof(sc));
    quantity = (unsigned long long int)pow(2, (sizeof(sc)*8)); // What is happening?
    printf("The range of a signed char is %hhd to %hhd\n", (sc-(quantity/2)), (sc+(quantity/2)-1));
    printf("A signed char can store %llu unique values\n\n", quantity);
    // Display information for unsigned short int data type
    printf("An unsigned short int is %d bytes\n", sizeof(usi));
    printf("The range of an unsigned short int is %hhu to %hhu\n", usi, (usi-1));
    quantity = (unsigned short int)(usi-1) + 1;    // What does this line do?
    printf("An unsigned short int can store %llu unique values\n\n", quantity);
    // Display information for signed short int data type
    printf("A signed short int is %d bytes\n", sizeof(ssi));
    quantity = (unsigned long long int)pow(2, (sizeof(ssi)*8)); // What is happening?
    printf("The range of a signed short int is %hhd to %hhd\n", (ssi-(quantity/2)), (ssi+(quantity/2)-1));
    printf("A signed short int can store %llu unique values\n\n", quantity);
    // Display information for unsigned int data type
    printf("An unsigned int is %d bytes\n", sizeof(ui));
    printf("The range of an unsigned int is %hhu to %hhu\n", ui, (ui-1));
    quantity = (unsigned int)(ui-1) + 1;    // What does this line do?
    printf("An unsigned int can store %llu unique values\n\n", quantity);
    // Display information for signed int data type
    printf("A signed int is %d bytes\n", sizeof(si));
    quantity = (unsigned long long int)pow(2, (sizeof(si)*8)); // What is happening?
    printf("The range of a signed int is %hhd to %hhd\n", (si-(quantity/2)), (si+(quantity/2)-1));
    printf("A signed int can store %llu unique values\n\n", quantity);
    // Display information for unsigned long int data type
    printf("An unsigned long int is %d bytes\n", sizeof(uli));
    printf("The range of an unsigned long int is %hhu to %hhu\n", uli, (uli-1));
    quantity = (unsigned long int)(uli-1) + 1;    // What does this line do?
    printf("An unsigned long int can store %llu unique values\n\n", quantity);
    // Display information for signed long int data type
    printf("A signed long int is %d bytes\n", sizeof(sli));
    quantity = (unsigned long long int)pow(2, (sizeof(sli)*8)); // What is happening?
    printf("The range of a signed long int is %hhd to %hhd\n", (sli-(quantity/2)), (sli+(quantity/2)-1));
    printf("A signed long int can store %llu unique values\n\n", quantity);
    // Display information for unsigned long long int data type
    printf("An unsigned long long int is %d bytes\n", sizeof(ulli));
    printf("The range of an unsigned long long int is %hhu to %hhu\n", ulli, (ulli-1));
    quantity = (unsigned long long int)(ulli-1) + 1;    // What does this line do?
    printf("An unsigned long long int can store %llu unique values\n\n", quantity);
    // Display information for signed long long int data type
    printf("A signed long long int is %d bytes\n", sizeof(slli));
    quantity = (unsigned long long int)pow(2, (sizeof(slli)*8)); // What is happening?
    printf("The range of a signed long long int is %hhd to %hhd\n", (slli-(quantity/2)), (slli+(quantity/2)-1));
    printf("A signed long long int can store %llu unique values\n\n", quantity);
    return(0);
}

Project 1 or as I like to call it Project2.c and Project2.1.c

#include<stdio.h>
#include<stdlib.h>
 
int main()
{
        FILE *message, *key, *cipher;
        char c, fname[] = "message.txt";
        char code[] = "key.txt";
        int keyvalue;
 
        message = fopen(fname, "r");
        key = fopen(code, "r");
        cipher = fopen("cipher.txt", "w");
 
        c = fgetc(message);
        fscanf(key,"%d",&keyvalue);
 
        printf("Message is: ");
 
        while(c != EOF)
        {
                fprintf(stdout, "%c", c);
                c = fgetc(message);
        }
 
        fclose(message);
        message = fopen(fname, "r");
        c = fgetc(message);
 
        printf("Cipher is: ");
 
        while(c != EOF)
        {
                if((c >= 65) && (c <= 'Z'))
                        c = c + keyvalue;
                else if((c >= 'a') && (c <= 'z'))
                        c = c + keyvalue;
 
                fprintf(stdout, "%c", c);
                fprintf(cipher, "%c", c);
                c = fgetc(message);
        }
        fclose(message);
        fclose(key);
        return(0);
}

#include<stdio.h>
#include<stdlib.h>
 
int main()
{
        FILE *cipher, *key, *decipher;
        char c, fname[] = "cipher.txt";
        char code[] = "key.txt";
        int keyvalue;
 
        cipher = fopen(fname, "r");
        key = fopen(code, "r");
        decipher = fopen("decipher.txt", "w");
 
        c = fgetc(cipher);
        fscanf(key,"%d",&keyvalue);
 
        printf("Cipher is: ");
 
        while(c != EOF)
        {
                fprintf(stdout, "%c", c);
                c = fgetc(cipher);
        }
 
        fclose(cipher);
        cipher = fopen(fname, "r");
        c = fgetc(cipher);
 
        printf("Decipher is: ");
 
        while(c != EOF)
        {
                if((c >= 65) && (c <= 'Z'))
                        c = c - keyvalue;
                else if((c >= 'a') && (c <= 'z'))
                        c = c - keyvalue;
 
                fprintf(stdout, "%c", c);
                fprintf(decipher, "%c", c);
                c = fgetc(cipher);
        }
        fclose(cipher);
        fclose(key);
        return(0);
}

What will happen if I take the ; off the end of a statement and try to compile the program.

lab46

Based on what I have learned thus far about c programming I think there would be an error in trying to compile the program.

I believe it would be considered a syntax error and the would be the reason there would be an error in trying to compile.

I am going to experiment on a hello world program we wrote in class this semester on lab46

lab46:~$ nano hello.c
lab46:~$ gcc -o hello hello.c
hello.c: In function 'main':
hello.c:5: error: expected ';' before 'return'
lab46:~$

Based on the data collected:

• Was your hypothesis correct?

yeah I am pretty good.

• Was your hypothesis not applicable?

it was applicable

• Is there more going on than you originally thought? (shortcomings in hypothesis)

no sir.

• What shortcomings might there be in your experiment?

intelligence.

• What shortcomings might there be in your data?

data is good.

make sure you put ; at the end of applicable statements.

What happens if you do not include a return; at the end of your program/function.

lab46

I am not entirely sure I am assuming I will get some sort of syntax error but to be sure I will have to run it to find out.

I am going to use my hello world! program once again that is deployed on lab46

lab46:~$ nano hello.c
lab46:~$ gcc -o hello hello.c
lab46:~$ nano hello.c
lab46:~$ ./hello
Hello, World!

Based on the data collected:

• Was your hypothesis correct?

No sadly I was wrong the program still ran and now I feel foolish.

• Was your hypothesis not applicable?

it was.

• Is there more going on than you originally thought? (shortcomings in hypothesis)

apparently :O

• What shortcomings might there be in your experiment?

intelligence.

• What shortcomings might there be in your data?

none.

The program still ran and complied with the return; statement line removed.

I am going to attempt to add the multiplication portion of project 2 into project 2.

I used the other functions addition and subtraction that I had help writing, more so addition because I figured add and multiply are alike in common sense than subtraction.

The goal is that it will work in the program just the way the other functions do and multiply my 4 digit numbers correctly. oh yeah and compile. hopefully.

I wrote the code (at least it seems like working code to me) into the program and I will attempt to compile it and run it on lab46

lab46:~/src/cprog$ nano bignum.c
lab46:~/src/cprog$ gcc -o bignum bignum.c
lab46:~/src/cprog$ ./bignum
How many digits are in your largest number?
4
Please enter 1 to Add, 2 to Subtract, 3 to Multiply, 4 to Divide
3
Enter your first number
0010
Please enter your second number
0010
01870
lab46:~/src/cprog$

Based on the data collected:

• Was your hypothesis correct?

no it was not my program told me 10×10 = 1870

• Was your hypothesis not applicable?

it was.

• Is there more going on than you originally thought? (shortcomings in hypothesis)

i have no idea.

• What shortcomings might there be in your experiment?

knowledge of how to program

• What shortcomings might there be in your data?

the intended answer.

I did not get the correct answer, I will have to figure it again a better way that produces the intended answer.