/* Largest prime factor Problem 3 Published on Friday, 2nd November 2001, 12:00 pm; Solved by 256800 The prime factors of 13195 are 5, 7, 13 and 29. What is the largest prime factor of the number 600851475143 ? By: dbk */ #include #define CALCULAR 600851475143 #define MAX 1000000 int main(int argc, char const *argv[]) { long res = 0; long valor = CALCULAR; for (int i = 2; i < MAX; i++) { while ( valor % i == 0) { valor /= i; res = i; } } printf("Mayor factor primo: %ld\n", res); return 0; }