Question

#include <stdio.h>

#include <stdlib.h>

#include <time.h>

int main() {   

srand(time(NULL)); // randomize

int *a; // pointer to array

int i, n;

printf("Size of array:");

scanf("%d", &n);

/* memory allocation */

a = (int*)malloc(n*sizeof(int));

/* array generating */

for (i = 0; i < n; i++) a[i] = rand()%101;

/* output */

for (i = 0; i<n; i++) printf("a[%d] = %d ", i, a[i]);

putchar('\n');

free(a);

return 0;  

}

Using the above code please do it to me following

334423. #1: Study Programming at the Kernel Level
        Write a program that creates an array of 100 random numbers from 0-99. The program sums the random numbers and prints the sum. It then writes the numbers to a new file using open, close and write.
        Other requirements:

1. Input—The program has no input data (it uses standard function to generate sequence of random numbers).
2. Output—The program prints the sum of the array. The program creates a file called numbers.XXXX where XXXX is the sum of the numbers in the file.
3. Program structure—The program has needs only one function: int main(void)

Hints:

Remember to initialize any sum variable to 0

rand() will return a random number too big for 0-99. Use modulo to reduce the range.

rand() needs to be initialized with a seed. You can use: srand(time(0));

334423. #2: Write a program that looks in the current directory for files that match the pattern “numbers.XXXX”. For each file, open the file and read the file. You can assume that the file will contain 100 integers. Sum the integers. Print the filename and the sum of the integers.

Hints:

Make a function to deal with open/read/sum/print/close.

opendir() requires a starting directory. You want to start where in the current directory.

You need to loop over the directory entries. This is similar to walking a linked list.

You want to check every file entry to see if it starts with “numbers.”

Answer 1

CODE TO COPY ALONG WITH SCREENSHOTS ARE PROVIDED BELOW:

(FOR INDENTS REFER TO SCREENSHOTS)

<<<<<<<<<<<-------------SOLUTION FOR RZRK #1--------------------------->>>>>>>>>>>>>>>>>.

SCREENSHOTS OF CODE:

OUTPUT SCREENSHOT:

After running the program txt file gets created.

(Each time code will run it will output the sum of random numbers like output screenshot above, And it will create txt file containing 100 random numbers in each file)

CODE FOR COPYING :

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

int main(void)
{

char s1[] = "numbers.";
char s2[10];
char s3[] = ".txt";

int sum = 0;
int a[100];

srand ( time(NULL) );

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

a[i] = rand()%101;
}

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

sum = sum + a[i];
}
sum = sum + a[99]; /*adding last number to sum as it didnt got added in loop*/

printf("SUM : %d\n",sum);

sprintf(s2,"%d",sum); /*converting sum to a string */

strcat(s1,s2); /*adding all strings together and storing into s1 */
strcat(s1,s3);

FILE *fp;
fp = fopen(s1,"w"); /*creating file */

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

fprintf(fp,"%d ",a[i]); /*storing numbers into file */
}
fclose(fp);

return 0;
}

<<<<<<<<<<<<<<<<<<<<----------------SOLUTION FOR RZRK #2 ----------------->>>>>>>>>>>>>>>

SCREENSHOTS:

output screeenshots:

Code to copy :

#include <stdbool.h>
#include <stdio.h>
#include <dirent.h>

bool StartsWith(const char *a, const char *b)
{
if(strncmp(a, b, strlen(b)) == 0) return 1;
return 0;
}
void action(const char *s){

FILE *file = fopen(s,"r");
int sum = 0;
int x;
while(!feof(file))

{

fscanf(file,"%d",&x);

sum+=x;

}
fclose(file);
printf("FILE_NAME: %s\n",s);
printf("SUM: %d\n\n",sum);

}

int main(void)
{
struct dirent *de; // Pointer for directory entry

// opendir() returns a pointer of DIR type.
DIR *dr = opendir(".");

// for readdir()
while ((de = readdir(dr)) != NULL){
if(StartsWith(de->d_name,"numbers.")){
action(de->d_name);

}
}
closedir(dr);
return 0;
}