C Programming: Find all prime factors of a given integer

C Programming Mathematics: Exercise-35 with Solution

Write a C program that accepts an integer and find all prime factors of the integer.

Prime factors of a number are those factors that are prime numbers. 2 and 4 are factors of 4, where 2 is considered the prime factor.

Test Data:
(77) -> 7, 11
(12) -> 2, 2, 3
(45) -> 3, 3, 5

Sample Solution:

C Code:

#include <stdio.h>
#include <math.h>

int main(void) {
  int n;
  printf("Input an integer: ");
  scanf("%d", &n);
	  if (n>0)
	  {	
       while (n%2==0) 
        { 
          printf("2 "); 
            n /= 2; 
        }   
        for (int i = 3; i <= sqrt(n); i+= 2) 
        { 
            while (n%i == 0) 
            { 
               printf("%d ",i);
                n /= i; 
            } 
        } 
        if (n > 2) 
            printf("%d",n); 
      }
	}

Sample Output:

Input an integer: 78
2 3 13

Flowchart:

C Programming Code Editor:

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