In this program, You will learn how to find an average of 5 subjects in C.

```
Some list of prime numbers is: 2 3 5 7 11 13 17
```

```
#include<stdio.h>
int main() {
int arr[10], i, s, j, p, sum = 0;
printf("Enter size of an array:");
scanf("%d", &s);
printf("Enter array elements:");
for (i = 0; i < s; i++) {
scanf("%d", &arr[i]);
}
for (i = 0; i < s; i++) {
j = 2;
p = 1;
while (j < arr[i]) {
if (arr[i] % j == 0) {
p = 0;
break;
}
j++;
}
if (p == 1)
sum = sum + arr[i];
}
printf("Sum of prime numbers:%d", sum);
return 0;
}
```

```
Enter size of an array:5
Enter array elements:2 3 4 5 6
Sum of prime numbers:10
```