- C Programming Examples
- C Programming Examples
- C Print Hello World
- C Get Input from User
- C Print Integer
- C Add Two Numbers
- C Check Even or Odd
- C Check Prime or Not
- C Check Alphabet or Not
- C Check Vowel or Not
- C Check Leap Year or Not
- C Check Reverse equal Original
- C Add Subtract Multiply Divide
- C Make Calculator
- C Add Digits of Number
- C Calculate Average, Percentage
- C Calculate Arithmetic Mean
- C Calculate Student Grade
- C Print Table of Number
- C Print Prime Numbers
- C Add n Numbers
- C Interchange Numbers
- C Reverse a Number
- C Swap Two Numbers
- C Count Positive Negative Zero
- C Find Largest of Two Numbers
- C Find Largest of Three Numbers
- C Find Factorial of Number
- C Find LCM & HCF
- C Find LCM of n Numbers
- C Find HCF of n Numbers
- C Area & Perimeter of Square
- C Area & Perimeter of Rectangle
- C Area & Circumference of Circle
- C Convert Fahrenheit to Celsius
- C Convert Celsius to Fahrenheit
- C Print ASCII Value
- C Print Fibonacci Series
- C Check Palindrome or Not
- C Check Armstrong or Not
- C Generate Armstrong Numbers
- C Find nCr and nPr
- C Convert Decimal to Binary
- C Convert Decimal to Octal
- C Convert Decimal to Hexadecimal
- C Convert Binary to Decimal
- C Convert Binary to Octal
- C Convert Binary to Hexadecimal
- C Convert Octal to Decimal
- C Convert Octal to Binary
- C Convert Octal to Hexadecimal
- C Convert Hexadecimal to Decimal
- C Convert Hexadecimal to Binary
- C Convert Hexadecimal to Octal
- C Pattern Printing Programs
- C Print Diamond Pattern
- C Print Floyd's Triangle
- C Print Pascal's Triangle
- C Print Smiling face
- C 1D Array Programs
- C Linear Search
- C Binary Search
- C Add Two Numbers using Pointer
- C Find Largest Element in Array
- C Find Smallest Element in Array
- C Reverse an Array
- C Insert Element in Array
- C Delete Element from Array
- C Merge Two Arrays
- C Bubble Sort
- C Selection Sort
- C Insertion Sort
- C 2D Array Programs
- C Add Two Matrices
- C Subtract Two Matrices
- C Transpose a Matrix
- C Multiply Two Matrices
- C 3D Array Programs
- C Print String
- C Find Length of String
- C Compare Two String
- C Copy a String
- C Concatenate String
- C Reverse a String
- C Delete Vowels from String
- C Delete Word from String
- C Find Frequency of Character
- C Count Word in String
- C Remove Spaces from String
- C Sort a String
- C Uppercase to Lowercase
- C Lowercase to Uppercase
- C Swap Two Strings
- C Check Anagram or Not
- C Generate Random Numbers
- C Read a File
- C Write Content to File
- C Read & Display File
- C Copy a File
- C Merge Two Files
- C List Files in Directory
- C Delete a File
- C Encrypt & Decrypt a File
- C Print Date
- C Get IP Address
- C Shutdown Computer
- C More Programs
- C Check Palindrome String
- C Inches to Centimetres
- C Kilogram to Gram
- C Count Even Odd
- C Count Vowels Consonants
- C Find Profit Loss
- C Sum All Matrix Elements
- C First & Last Digit Sum
- C Largest Element in Matrix
- C Pass Array to Function
- C Address of Variable
- C Array Element at Even
- C Array Element at Odd
- C Print Even Array Elements
- C Print Odd Array Elements
- C Reverse File
- C Print Message with Time
- C Print Number in Words
- C Print Successive Character
- C Sum of their Square
- C Replace Vowel in String
- C Sort Words in Ascending
- C Sort Words in Descending
- C Sort String in Alphabetical
- C Programming Tutorial
- C Tutorial
- C Programming Library
- C Standard Library
- C Programming Test
- C Programming Test
- Give Online Test
- All Test List

In this tutorial, you will learn and get code about printing of prime numbers in following ways:

- Print Prime Numbers from 1 to 50
- Print Prime Numbers in given Range

But before going through the program, let's first understand about prime number.

Prime number is a number that can only be divisible by 1 and the number itself. That is, if a number is not
divisible by anything except 1 and the number itself, then it is called as prime number. For example, **13, 23,
37** are prime numbers. Because 13 is not divisible by anything except 1 and 13. Like this, 23 is also not
divisible by anything except 1 and 23.

The question is, **write a program in C to print all prime number from 1 to 50**. Here is its answer:

// ----codescracker.com---- #include<stdio.h> #include<conio.h> int main() { int i, count=0, j; printf("Prime numbers between 1 to 50 are:\n"); for(i=1; i<=50; i++) { for(j=2; j<i; j++) { if(i%j==0) { count++; break; } } if(count==0 && i!=1) printf("%d\n", i); count = 0; } getch(); return 0; }

As the program was written under **Code::Blocks** IDE, therefore after successful build and run, here is the
sample run:

- Take a variable say
**count**and initialize it with 0 at beginning of the program - Create a for loop and start it from 1 to 50
- Inside the
**for**loop, create another**for**loop with different loop variable say**j** - Start inner
**for**loop with 2 and run upto one less than the value of outer for loop's variable say**i** - Then inside the second
**for**loop, create**if**block to check whether the number is divisible by any number from 2 to one less than the number. That is if the number is 17, then check whether it is divisible with any of the number from 2, 3, 4, ...., 15, 16 or not - If it is, then increment the value of
**count**and use break statement to exit from the inner**for**loop - Otherwise continue checking divisibility upto one less than the number. That is, if the number is 17, then check upto 16 then
exit from the loop, and check for next number say
**18** - On exiting from the inner
**for**loop with or without using**break**statement - Check whether the variable
**count**holds its original value (that is 0) or not - If it holds, then the number is not divisible by anything, it means that the number is prime number
- And if the number is prime number, then print the number as output and continue
- If it does not holds its original value (that is 0), then the number is divisible by something, it means that the number is not a prime number
- Never forgot to initialize 0 to
**count**at last of the first**for**loop

Now let's modify the above program with adding some extra features. Here in this program we've added to allow user
to provide the range under which all the prime numbers gets printed. That is, this program will ask from the user to
enter starting number say **10** and ending number say **100** to print all the prime numbers present in between
these two numbers say 10 and 100 as shown in the program given below:

// ----codescracker.com---- #include<stdio.h> #include<conio.h> int main() { int i, count=0, j, start, end; printf("Enter starting number: "); scanf("%d", &start); printf("Enter ending number: "); scanf("%d", &end); printf("\nPrime numbers between %d to %d are:\n", start, end); for(i=start; i<=end; i++) { for(j=2; j<i; j++) { if(i%j==0) { count++; break; } } if(count==0 && i!=1) printf("%d ", i); count = 0; } getch(); return 0; }

Here is the first snapshot of the sample run:

Now supply any number say 10 as starting number and then 100 as ending number to print all the prime numbers present in between these two numbers as shown in the second snapshot of the sample run: