C program to determine prime number

 

 Code 1:C program to determine prime number

#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:7

  7 is a prime number

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Code 2: c program to generate n prime numbers

#include<stdio.h>

int main(){

    int number,i,count,n;

    printf("Enter the max range of prime numbers you want ");

    scanf("%d",&n);

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

         count = 0;

         for(i=2;i<=number/2;i++){

             if(number%i==0){

                 count++;

                 break;

             }

        }

        

         if(count==0 && number!= 1)

             printf("%d ",number);

    }

  

   return 0;

}

Sample output:

Enter the max range of prime numbers you want: 20

2 3 5 7 11 13 17 19

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Code 3:How to print prime numbers from 1 to 100 in c

#include<stdio.h>

int main(){

    int number,i,count;

  

    for(number = 1;number<=100;number++){

         count = 0;

         for(i=2;i<=number/2;i++){

             if(number%i==0){

                 count++;

                 break;

             }

        }

        

         if(count==0 && number!= 1)

             printf("%d ",number);

    }

  

   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

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Code 4:Sum of prime numbers from 1 to 100 in c

#include<stdio.h>

int main(){

    int num,i,count,sum=0;

    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)

             sum = sum + num;

    }

    printf("Sum of prime numbers is: %d ",sum);

  

   return 0;

}

  

Output:

Sum of prime numbers is: 1060

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Code 5:C program to find prime numbers using while loop

#include<stdio.h>

int main(){

   int num,i,count,min,max;

printf("Enter minimum range: ");

    scanf("%d",&min);

    printf("Enter maximum 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;

}

output:

Enter minimum range: 20

Enter maximum range: 30

        23,29

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Code 6:C program to find sum of prime numbers

#include<stdio.h>

int main(){

    int num,i,count,min,max,sum=0;

     printf("Enter minimum range: ");

     scanf("%d",&min);

    printf("Enter maximum 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;

}

output:

Enter min range: 20

Enter max range: 30

 Sum of prime numbers is:52

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Code 7:C program to find prime numbers using for loop

#include<stdio.h>

int main(){

    int num,i,count,min,max;

     printf("Enter minimum range: ");

     scanf("%d",&min);

    printf("Enter maximum 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;

}

output:

Enter minimum range: 20

Enter maximum range: 30

        23,29