Create number-of-ways-where-square-of-number-is-equal-to-product-of-two-numbers.cpp

Author: kamyu104

C++/number-of-ways-where-square-of-number-is-equal-to-product-of-two-numbers.cpp

@@ -0,0 +1,30 @@
+// Time:  O(m * n)
+// Space: O(m + n)
+
+class Solution {
+public:
+    int numTriplets(vector<int>& nums1, vector<int>& nums2) {
+        int result = 0;
+        for (const auto& n : nums1) {
+            result += twoProduct(nums2, static_cast<int64_t>(n) * n);
+        }
+        for (const auto& n : nums2) {
+            result += twoProduct(nums1, static_cast<int64_t>(n) * n);
+        }
+        return result;
+    }
+
+private:
+    int twoProduct(const vector<int>& nums, int64_t i) {
+        unordered_map<int, int> lookup;
+        int count = 0;
+        for (const auto& num : nums) {
+            if (i % num) {
+                continue;
+            }
+            count += lookup[i / num];
+            ++lookup[num];
+        }
+        return count;
+    }  
+};