# C Programs on flow control statements (if, switch, loop, break and continue)-2

Printing numbers from 1 to given number.
Intput:  Enter a number : 10
Output: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
Program:
main()
{
int num,i;
printf(“Enter a number”);
scanf(“%d”,&num);
printf(“printing numbers from 1 to %dn”,num);
for(i=1;i<=num;i++)
{
printf(“%d “,i);
}

}

Printing odd numbers from 1 to given number.
Intput:  Enter a number : 10
Output: 1,3, 5, 7, 9
Program:
main()
{
int num,i;
printf(“Enter a number”);
scanf(“%d”,&num);
printf(“printing numbers from 1 to %dn”,num);
for(i=1;i<=num;i++)
{
if(num%2==1)
printf(“%d “,i);
}
}
Printing even numbers from 2 to given number.
Intput:  Enter a number : 10
Output:  2, 4, 6, 8, 10
Program:
main()
{
int num,i;
printf(“Enter a number”);
scanf(“%d”,&num);
printf(“printing numbers from 1 to %dn”,num);
for(i=1;i<=num;i++)
{
if(num%2==0)
printf(“%d “,i);
}

}
C Program to Calculate Sum of Natural Numbers
Intput:  Enter a number : 10
Output: 55
Program:
main()
{
int num,i,sum=0;
printf(“Enter a number”);
scanf(“%d”,&num);

for(i=1;i<=num;i++)
{
sum=sum+i;
}
printf(“Sum of natural numbers from 1 to %d is %d”,num,sum);
}
Printing factors of a given number
Intput:  Enter a number : 10
Output: 1, 2, 5, 10
Program:
main()
{
int num,i;
printf(“Enter a number”);
scanf(“%d”,&num);
printf(“printing factors of %dn”,num);
for(i=1;i<=num;i++)
{
if(num%i==0)
printf(“%d “,i);
}
}
Printing number of factors of a given number
Intput:  Enter a number : 10
Output:4
Program:
main()
{
int num,i,count=0;
printf(“Enter a number”);
scanf(“%d”,&num);

for(i=1;i<=num;i++)
{
if(num%i==0)
count++;
}
printf(“Number of factors of %d are %dn”,num,count);
}
C Program to Check Whether a Number is Prime or Not
Intput:  Enter a number : 10
Output:not a prime
Program:
main()
{
int num,i,count=0;
printf(“Enter a number”);
scanf(“%d”,&num);

for(i=1;i<=num;i++)
{
if(num%i==0)
count++;
}
if(count==2)
printf(“Prime”);
else
printf(“not a prime”);
}
Printing sum of the factors of a given number
Intput:  Enter a number : 10
Output:18
Program:
main()
{
int num,i,sum=0;
printf(“Enter a number”);
scanf(“%d”,&num);

for(i=1;i<=num;i++)
{
if(num%i==0)
sum=sum+i;
}
printf(“sum of factors of %d are %dn”,num,sum);
}
Write a c program to check given number is perfect number or not.
In number theory, a perfect number is a positive integer that is equal to the sum of its proper positive divisors, that is, the sum of its positive divisors excluding the number itself (also known as its aliquot sum).
Intput:  Enter a number : 6
Output: Perfect Number
Program:
main()
{
int num,i,sum=0;
printf(“Enter a number”);
scanf(“%d”,&num);

for(i=1;i<num;i++)
{
if(num%i==0)
sum=sum+i;
}
if(sum==num)
printf(“perfect number”);
else
printf(“Not a perfect number”);
}