Question:Determining if a number is prime in c 

#include<stdio.h>

int main(){

    int num,i,count=0;
    printf("Enter a number: ");
    scanf("%d",&num);
    for(i=2;i<=num/2;i++){
        if(num%i==0){
         count++;
            break;
        }
    }
   if(count==0 && num!= 1)
        printf("%d is a prime number",num);
   else
      printf("%d is not a prime number",num);
   return 0;
}
Sample output:
Enter a number: 5
5 is a prime number

Question:How to find prime numbers from 1 to 100 in c 

#include<stdio.h>

int main(){
    int num,i,count;
  
    for(num = 1;num<=100;num++){
         count = 0;

         for(i=2;i<=num/2;i++){
             if(num%i==0){
                 count++;
                 break;
             }
        }
        
         if(count==0 && num!= 1)
             printf("%d ",num);
    }
  
   return 0;
}
Output:
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97

Question:Write a c program to generate n prime numbers 

#include<stdio.h>

int main(){

    int num,i,count,n;
    printf("Enter max range: ");
    scanf("%d",&n);

    for(num = 1;num<=n;num++){

         count = 0;

         for(i=2;i<=num/2;i++){
             if(num%i==0){
                 count++;
                 break;
             }
        }
        
         if(count==0 && num!= 1)
             printf("%d ",num);
    }
  
   return 0;
}
Sample output:
Enter max range: 50
2 3 5 7 11 13 17 19 23 29 31 37 41 43 47

Question:C code to display prime numbers within a range 

#include<stdio.h>

int main(){

    int num,i,count,min,max;

     printf("Enter min range: ");
     scanf("%d",&min);

    printf("Enter max range: ");
    scanf("%d",&max);

    for(num = min;num<=max;num++){

         count = 0;

         for(i=2;i<=num/2;i++){
             if(num%i==0){
                 count++;
                 break;
             }
        }
        
         if(count==0 && num!= 1)
             printf("%d ",num);
    }
  
   return 0;
}
Alternate with while loop
#include<stdio.h>

int main(){

   int num,i,count,min,max;

printf("Enter min range: ");
    scanf("%d",&min);

    printf("Enter max range: ");
    scanf("%d",&max);

    num = min;
    while(num<=max){

         count = 0;
         i=2;

         while(i<=num/2){
             if(num%i==0){
                 count++;
                 break;
             }
             i++;
        }
        
         if(count==0 && num!= 1)
             printf("%d ",num);

         num++;
    }
  
   return 0;
}
Sample output:
Enter min range: 10
Enter max range: 50
11 13 17 19 23 29 31 37 41 43 47

Question:C program to find sum of prime numbers within a range. 

#include<stdio.h>

int main(){

    int num,i,count,min,max,sum=0;

     printf("Enter min range: ");
     scanf("%d",&min);

    printf("Enter max range: ");
    scanf("%d",&max);

    for(num = min;num<=max;num++){

         count = 0;

         for(i=2;i<=num/2;i++){
             if(num%i==0){
                 count++;
                 break;
             }
        }
        
         if(count==0 && num!= 1)
             sum = sum + num;
    }

    printf("Sum of prime numbers is: %d ",sum);
  
   return 0;
}
Sample output:
Enter min range: 50
Enter max range: 100
Sum of prime numbers is: 732

Question:C program to check even or odd 

#include<stdio.h>

int main(){

    int number;
  
    printf("Enter any integer: ");
    scanf("%d",&number);

    if(number % 2 ==0)
         printf("%d is even number.",number);
    else
         printf("%d is odd number.",number);
  
    return 0;

}
Sample output:
Enter any integer: 5
5 is odd number.

Question:Display odd numbers in c within a range 

#include<stdio.h>

int main(){

    int number;
    int min,max;
  
    printf("Enter the minimum range: ");
    scanf("%d",&min);

    printf("Enter the maximum range: ");
    scanf("%d",&max);

    printf("Odd numbers in given range are: ");
    for(number = min;number <= max; number++)

         if(number % 2 !=0)
             printf("%d ",number);
  
    return 0;

}
Sample output:
Enter the minimum range: 1
Enter the maximum range: 20
Odd numbers in given ranges are: 1 3 5 7 9 11 13 15 17 19

Question:C program to display separate even and odd numbers list within a range. 

#include<stdio.h>

int main(){

    int number;
    int min,max;
  
    printf("Enter the minimum range: ");
    scanf("%d",&min);

    printf("Enter the maximum range: ");
    scanf("%d",&max);

    printf("Odd numbers in given range are: ");
    for(number = min;number <= max; number++)

         if(number % 2 !=0)
             printf("%d ",number);

    printf("\nEven numbers in given range are: ");
    for(number = min;number <= max; number++)

         if(number % 2 ==0)
             printf("%d ",number);
  
    return 0;
}
Sample output:
Enter the minimum range: 1
Enter the maximum range: 20
Odd numbers in given ranges are: 1 3 5 7 9 11 13 15 17 19
Even numbers in given ranges are: 2 4 6 8 10 12 14 16 18 20

Question:Sum of odd numbers in c within a range. 

#include<stdio.h>

int main(){

    int number;
    int min,max;
    long sum =0;
  
    printf("Enter the minimum range: ");
    scanf("%d",&min);

    printf("Enter the maximum range: ");
    scanf("%d",&max);

    for(number = min;number <= max; number++)
         if(number % 2 !=0)
             sum = sum + number;

    printf("Sum of odd numbers in given range is: %ld",sum);
  
    return 0;

}
Sample output:
Enter the minimum range: 1
Enter the maximum range: 100
Sum of odd numbers in given range is: 2500

Question:c program to sum odd and even numbers within a range 

#include<stdio.h>

int main(){

    int number;
    int min,max;
    long odd_sum =0,even_sum = 0;
  
    printf("Enter the minimum range: ");
    scanf("%d",&min);

    printf("Enter the maximum range: ");
    scanf("%d",&max);

    for(number = min;number <= max; number++)
         if(number % 2 != 0)
             odd_sum = odd_sum + number;
         else
             even_sum = even_sum + number;

    printf("Sum of even numbers in given range is: %ld\n",even_sum);
    printf("Sum of odd numbers in given range is: %ld",odd_sum);
  
    return 0;

}
Sample output:
Enter the minimum range: 1
Enter the maximum range: 10
Sum of even numbers in given range is: 30
Sum of odd numbers in given range is: 25