Create three-divisors.cpp

Author: kamyu104

C++/three-divisors.cpp

@@ -0,0 +1,15 @@
+// Time:  O(sqrt(n))
+// Space: O(1)
+
+class Solution {
+public:
+    bool isThree(int n) {
+        int cnt = 0;
+        for (int i = 1; i <= n / i && cnt <= 3; ++i) {
+            if (n % i == 0) {
+                cnt += (i == n / i) ? 1 : 2;
+            }
+        }
+        return cnt == 3;
+    }
+};