Write a C program to print all Prime numbers between 1 to n using loop. C program to print all prime number within a given range. How to print all prime numbers between given interval using loop in C program.

Input lower limit: 1

Input upper limit: 10

Output prime numbers between 1-10: 2, 3, 5, 7

You can also check this program using the concept of functions - C program to find all prime numbers between 1 to n using functions.

Before printing all primes between 1 to n you must first know how to check prime numbers in C.

Happy coding ;)

**Example:**Input lower limit: 1

Input upper limit: 10

Output prime numbers between 1-10: 2, 3, 5, 7

You can also check this program using the concept of functions - C program to find all prime numbers between 1 to n using functions.

### Required knowledge

Basic C programming, If else, For loop, Nested loops#### Prime number

Prime number is a positive integer greater than 1 that is only divisible by 1 and self.**Example:**2, 3 , 5, 7, 11 are the first five prime numbersBefore printing all primes between 1 to n you must first know how to check prime numbers in C.

### Program to print prime numbers between 1 to n

/** * C program to print all prime numbers between 1 to n */ #include <stdio.h> int main() { int i, j, n, isPrime; //isPrime is used as flag variable /* Reads upper limit to print prime */ printf("Find prime numbers between 1 to : "); scanf("%d", &n); printf("\nAll prime numbers between 1 to %d are:\n", n); /* Finds all Prime numbers between 1 to n */ for(i=2; i<=n; i++) { /* Assume that the current number is Prime */ isPrime = 1; /* Check if the current number i is prime or not */ for(j=2; j<=i/2; j++) { /* * If i is divisible by any number other than 1 and self * then it is not prime number */ if(i%j==0) { isPrime = 0; break; } } /* If the number is prime then print */ if(isPrime==1) { printf("%d is Prime number\n", i); } } return 0; }

**Note:**For checking whether a number is Prime or not we just need to check that the number should not be divisible by any number between 2 to n-1. Apart from that you can also check between 2 to n/2. Since any number more than (n/2)+1 cannot be exactly divided by n except self n.

Output

Find prime numbers between 1 to : 100

All prime numbers between 1 to 100 are:

2 is Prime number

3 is Prime number

5 is Prime number

7 is Prime number

11 is Prime number

13 is Prime number

17 is Prime number

19 is Prime number

23 is Prime number

29 is Prime number

31 is Prime number

37 is Prime number

41 is Prime number

43 is Prime number

47 is Prime number

53 is Prime number

59 is Prime number

61 is Prime number

67 is Prime number

71 is Prime number

73 is Prime number

79 is Prime number

83 is Prime number

89 is Prime number

97 is Prime number

All prime numbers between 1 to 100 are:

2 is Prime number

3 is Prime number

5 is Prime number

7 is Prime number

11 is Prime number

13 is Prime number

17 is Prime number

19 is Prime number

23 is Prime number

29 is Prime number

31 is Prime number

37 is Prime number

41 is Prime number

43 is Prime number

47 is Prime number

53 is Prime number

59 is Prime number

61 is Prime number

67 is Prime number

71 is Prime number

73 is Prime number

79 is Prime number

83 is Prime number

89 is Prime number

97 is Prime number

Happy coding ;)

### You may also like

- Loop programming exercises index.
- C program to check whether a number is Prime number or not.
- C program to print all factors of a number.
- C program to print all Prime factors of a number.
- C program to check whether a number is Strong number or not.
- C program to check whether a number is Armstrong number or not.
- C program to check whether a number is Perfect number or not.
- C program to print all Strong numbers between 1 to n.
- C program to print all Armstrong number between 1 to n.
- C program to print all Perfect numbers between 1 to n.

4 not prime number

ReplyDeleteThanks @Akshay for observing. There was a small logical bug which has been removed.

Delete