Rota Hackathon

1. Program to Find the Sum of Digits of a Number

Expected Output:

Enter a number: 12345
Sum of digits: 15

#include <stdio.h>

int main() {
    int num, sum = 0;
    printf("Enter a number: ");
    scanf("%d", &num);

    while (num > 0) {
        sum = sum + num % 10;
        num = num / 10; 
    }

    printf("Sum of digits: %d\n", sum);
    return 0; 
}

2. Program to Check Whether a Number is Prime

Expected Output:

Enter a number: 29

29 is a prime number.

#include <stdio.h>

int main() {
    int num, i;
    printf("Enter a number: ");
    scanf("%d", &num);

    if (num <= 1) {
        printf("%d is not a prime number.\n", num);  
    }

    for(i = 2; i < num / 2; i++) {  
        if (num % i == 0) {
            printf("%d is not a prime number.\n", num); 
            break;
        }
    }

    if (i == num) {  
        printf("%d is a prime number.\n", num);
    }

    return 0;
}

3. Program to Print Fibonacci Sequence

Expected Output:

Enter the number of terms: 5
Fibonacci Series: 0 1 1 2 3

#include <stdio.h>

int main() {
    int n, i, t1 = 0, t2 = 1;
    printf("Enter the number of terms: ");
    scanf("%d", &n);

    printf("Fibonacci Series: ");
    for(i = 1; i < n; i++) {  
        printf("%d ", t1);  
        t1 = t1 + t2; 
        t2 = t1 + t2;  
    }

    return 0;  
}