[Hacker Rank]: Project Euler #3: Largest prime factor. Solved ✓

Author: Gonzalo Diaz

src/lib/exercises/src/hackerrank/projecteuler/euler003.cpp

@@ -10,7 +10,6 @@
 namespace hackerrank::projecteuler {
 
 long long prime_factor(long long n) {
-
   if (n < 2) {
     throw std::invalid_argument("n must be greater than 2");
   }
@@ -19,9 +18,9 @@ long long prime_factor(long long n) {
   long long max_prime_factor;
   bool mpf_initialized = false;
 
-  long long i = 2;
+  long i = 2;
 
-  while (i <= static_cast<long long>(sqrt(divisor))) {
+  while (static_cast<double>(i) <= sqrt(divisor)) {
     if (0 == divisor % i) {
       divisor = divisor / i;
       max_prime_factor = divisor;

src/tests/unit/lib/hackerrank/projecteuler/euler003.test.cpp

@@ -22,14 +22,12 @@ TEST_CASE("euler003 JSON Test Cases",
   json data = json::parse(f);
 
   for (auto testcase : data) {
-    int result = hackerrank::projecteuler::euler003(testcase["n"]);
+    long long result = hackerrank::projecteuler::euler003(testcase["n"]);
     CHECK(result == testcase["expected"]);
   }
 }
 
 TEST_CASE("euler003 Edge Cases", "[hackerrank] [projecteuler]") {
-
   CHECK_THROWS_AS(hackerrank::projecteuler::euler003(0), std::invalid_argument);
-
   CHECK_THROWS_AS(hackerrank::projecteuler::euler003(1), std::invalid_argument);
 }