Prime Number Manipulation

1. Write a C program to calculate the SUM and COUNT of Primes from a given range of numbers. Formatting required for the Input and Output statements.

Sample Input:

Range Start From: 1
End of Range: 10

Sample Output:

The Sum of Primes is: 11
Total Primes: 5

2. Write a C Program to Print all the Prime Numbers between 1 and 100. 

Sample Output:

1,  2,  3,  5,  7,  11,  13,  . . . . etc

3. WAP Program to get a range from user and give a list of prime numbers up to that number. And check whether the sum of all printed prime numbers are equal to the given input or not?

Sample Input: 10

Sample Output:

Prime list: 1, 2, 3, 5, 7

The sum is: 18

The sum is not equal to 10

1.                                                                                                                                                                 

main()
{
int a, b, c, n=0, start, end, sum=0;
printf("Range Start From: ");
scanf("%d", &start);
printf("End of Range: ");
scanf("%d", &end);

for(a=start;a<=end;a++)
{
c=1;
for(b=2;b<=a/2;b++)
{
if(a%b==0)
{
c=0;
break;
}
}
if(c==1)
{
sum+=a;
n++;
}
}
printf("The Sum of Primes is: %d\nTotal primes: %d", sum, n);
getch();
return 0;
}

2.                                                                                                                                                                  

main()
{
int a, b, c;

for(a=1;a<=100;a++)
{
c=1;
for(b=2;b<=a/2;b++)
{
if(a%b==0)
{
c=0;
break;
}
}
if(c==1)
{
printf("%d\t", a);
}
}
getch();
}

3.                                                                                                                                                                 


main()
{
int a, b, c,n,sum=0;
printf("Enter Range\n");
scanf("%d",&n);
printf("Prime list : ");
for(a=1;a<=n;a++)
{
c=1;
for(b=2;b<=a/2;b++)
{
if(a%b==0)
{
c=0;
break;
}
}
if(c==1)
{
printf("%d\t", a);
sum+=a;
}
}
printf("The sum is: %d",sum);

if (sum==n)
{
 printf("The sum is equal to %d",n);
}
else
{
printf("The sum is not equal to %d",n);
}

getch();
}
<< Go to Index Page >>