How to calculate sum of random numbers in between 0 to 100 using files in C Programming?

In this program, we are adding random numbers that are generated in between 0 and 100.

After every runtime, the result of sum of random numbers is different, i.e., we get a different result for every execution.

The logic we use to calculate the sum of random numbers in between 0 to 100 is −

for(i = 0; i <=99; i++){
   // Storing random numbers in an array.
   num[i] = rand() % 100 + 1;
   // calculating the sum of the random numbers.
   sum+= num[i];
}

First, we calculate the sum of random numbers and store that sum in a file. For that open file in write open and append the sum to the array file using fprintf.

fprintf(fptr, "Total sum of the array is %d
", sum);
//appending sum to the array file.

Example

#include<stdio.h>
#include<stdlib.h>
#include<time.h>
#define max 100
// Declaring the main function in the main header.
int main(void){
   srand(time(0));
   int i;
   int sum = 0, num[max];
   FILE *fptr;
   // Declaring the loop to generate 100 random numbers
   for(i = 0; i <=99; i++){
      // Storing random numbers in an array.
      num[i] = rand() % 100 + 1;
      // calculating the sum of the random numbers.
      sum+= num[i];
   }
   // intializing the file node with the right node.
   fptr = fopen("numbers.txt", "w");
   // cheching if the file pointer is null, check if we are going to exit or not.
   if(fptr == NULL){
      printf("Error!");
      exit(1);
   }
   fprintf(fptr, "Total sum of the array is %d
", sum); // appending sum to the array file.
   fclose(fptr); // closing the file pointer
}

Output

Run 1: Total sum of the array is 5224
Run 2: Total sum of the array is 5555
Note: after executing a text file is created in the same folder with number.txt
We have to open it; there we can see the sum of random numbers.