C Exercises: Find the largest prime factor of the number 438927456

Last update on May 27 2022 12:16:39 (UTC/GMT +8 hours)

C Programming Practice: Exercise-19 with Solution

The prime factors of 13195 are 5, 7, 13, 29.
Write a C programming to find the largest prime factor of the number 438927456?.

C Code:

#include <stdio.h>
int main(void)
{
  unsigned long long n = 438927456L;
  unsigned long long i;
  for (i = 2ULL; i < n; i++) {
  	//1ULL is 'unsigned long long
    while (n % i == 0) {
      n /= i;
    }
  }
  printf("%llu\n", n);
  return 0;
}

Sample Output:

Flowchart:

C Programming Code Editor:

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Previous: Write a C programming to find the sum of the even-valued terms from the terms in the Fibonacci sequence whose values do not exceed one million.
Next: Write a C programming to find the largest palindrome made from the product of two 3-digit numbers.

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C Programming: Tips of the Day

Static variable inside of a function in C

The scope of variable is where the variable name can be seen. Here, x is visible only inside function foo().

The lifetime of a variable is the period over which it exists. If x were defined without the keyword static, the lifetime would be from the entry into foo() to the return from foo(); so it would be re-initialized to 5 on every call.

The keyword static acts to extend the lifetime of a variable to the lifetime of the programme; e.g. initialization occurs once and once only and then the variable retains its value - whatever it has come to be - over all future calls to foo().

Ref : https://bit.ly/3fOq7XP