Transferring contents of an array to another in C - c

Question

I'm coding a program which accepts a number as a divisor and the other numbers from the user. My problem is with segregating the array where the ten entered numbers into two different arrays, one array is for numbers divisible by a divisor entered by the user and one is for non-divisible ones. I think I've got most of it down but whenever I try to display the contents of the array it would show a 0 at the end of the line. Also when none of the entered numbers are divisible it would dispaly "16 0 1" even if those numbers are not entered by the user.
Here's my code:
int main(){
int num, arr[size], div[size], nondiv[size], d=0, nd=0;
int divsize = 0;
int nondivsize = 0;
int arrsize = 0;
do{
printf("Enter a number within 1 and 5: ");
scanf("%d", &num);
if(num<1 || num>5)
printf("\nThe number you have entered is not within the given range.\n");
} while(num<1 || num>5);
printf("\nEnter ten numbers: \n");
for(int i=0; i<10; i++){
printf("Number %d: ", i+1);
scanf("%d", &arr[i]);
}
printf("\nEntered numbers: ");
for(int i=0; i<10; i++){
printf("%d ", arr[i]);
}
//calculates the arrays size of arr and displays it
for(int i; i<10; i++){
if(arr[i]!= 0)
arrsize++;
}
printf("\narrsize: %d\n", arrsize);
//Stores divisible and non-divisible inputs in to different arrays
for(int i=0; i<10; i++){
if(arr[i]%num == 0){
div[d] = arr[i];
d++;
}
else{
nondiv[nd] = arr[i];
nd++;
}
}
//calculates the number of elements in array div and displays it
for(int i=0; i<10; i++){
if(div[i] != 0){
divsize++;
}
}
printf("Number of divisible numbers: %d ", divsize);
printf("\nDivisible numbers: ");
for(int i=0; i<divsize; i++){
printf("%d ", div[i]);
}
}

Answer 1

I did some changes to your code and i think it works fine.....
in your code:
//calculates the number of elements in array div and displays it
for(int i=0; i<10; i++){
if(div[i] != 0){
divsize++;
}
}
i don't think this is necessary as you've already caluclated number of divisble and non divisble numbers and stored them in d and nd respectively (and) the numbers in the arrays div[] and nondiv[] in this loop:
for(int i=0; i<10; i++){
if(arr[i]%num == 0){
div[d] = arr[i];
d++;
}
else{
nondiv[nd] = arr[i];
nd++;
}
}
so while printing the number of divisible numbers and the divisible numbers array you can us d as parameter instead of divsize like this:
printf("Number of divisible numbers: %d ", d);//changed to d
printf("\nDivisible numbers: ");
for(int i=0; i<d; i++) //even here
{
printf("%d ", div[i]);
}
so to sum it all up, remove the last but one loop and change the
parameters of last loop from divsize to d in the last loop
*** and by the way I hope you declared size globally
so the code would be:
#include<stdio.h>
#define size 10 //i defined size globally here
int main()
{
int num, arr[size], div[size],nondiv[size],d=0, nd=0;
int arrsize = 0;
do{
printf("Enter a number within 1 and 5: ");
scanf("%d", &num);
if(num<1 || num>5)
printf("\nThe number you have entered is not within the given range.\n");
} while(num<1 || num>5);
printf("\nEnter ten numbers: \n");
for(int i=0; i<10; i++){
printf("Number %d: ", i+1);
scanf("%d", &arr[i]);
}
printf("\nEntered numbers: ");
for(int i=0; i<10; i++){
printf("%d ", arr[i]);
}
//calculates the arrays size of arr and displays it
for(int i=0; i<10; i++){
if(arr[i]!= 0)
arrsize++;
}
printf("\narrsize: %d\n", arrsize);
//Stores divisible and non-divisible inputs in to different arrays
for(int i=0; i<10; i++){
if(arr[i]%num == 0){
div[d] = arr[i];
d++;
}
else
{
nondiv[nd] = arr[i];
nd++;
}
}
printf("Number of divisible numbers: %d ", d);
printf("\nDivisible numbers: ");
for(int i=0; i<d; i++){
printf("%d ", div[i]);
}
}
-thank you

Answer 2

You declared a loop variable but didn't initialize it so its values is garbage value. Where you wrote
for(int i; i< size ;i++)
you should use i=0.
Other mistake is you can not declare size globally mean declare size as global variable and use as Loop variants means
for(int i=0;i< size;i++)
I also add commenting in your program where I change.
This loop isn't required, it makes the program too complex:
for(int i=0; i<10; i++){
if(div[i] != 0){
divsize++;
}
}
Because You already have counts of div array with the name of d.
Here is your updated Program
#include<stdio.h>
#include<conio.h>
#define size 10 // Every where you use hard coded 10 change it to size
int main(){
int num , arr[size], div[size], nondiv[size], d=0, nd=0;
int divsize = 0;
int nondivsize = 0;
int arrsize = 0;
do{
printf("Enter a number within 1 and 5: ");
scanf("%d", &num);
if(num<1 || num>5)
printf("\nThe number you have entered is not within the given range.\n");
} while(num<1 || num>5);
printf("\nEnter ten numbers: \n");
for(int i=0; i<10; i++){
printf("Number %d: ", i+1);
scanf("%d", &arr[i]);
}
printf("\nEntered numbers: ");
for(int i=0; i<10; i++){
printf("%d ", arr[i]);
}
//calculates the arrays size of arr and displays it
for(int i=0; i<10; i++){
// In loop variable you did'nt initialize i that's why it shows garbage value which is greater than 10000
if(arr[i]!= 0)
arrsize++;
}
printf("\narrsize: %d\n", arrsize);
//Stores divisible and non-divisible inputs in to different arrays
for(int i=0; i<10; i++){
if(arr[i]%num == 0){
div[d] = arr[i];
d++;
}
else{
nondiv[nd] = arr[i];
nd++;
}
}
//calculates the number of elements in array div and displays it
for(int i=0; i<10; i++){
if(div[i] != 0){
divsize++;
}
}
printf("Number of divisible numbers: %d ", d/*Here I just print d Because it is the count of divisible*/);
printf("\nDivisible numbers: ");
for(int i=0; i<d/*Here also used d */ ; i++){
printf("%d ", div[i]);
}
}