1. Formatting fixes.

2. Added new problem: Product of Array Except Self - 238.

include/leeter/h_index_274.hpp

@@ -1,20 +1,20 @@
-#include <vector>
 #include <algorithm>
-using std::vector;
+#include <vector>
 using std::sort;
+using std::vector;
 
 namespace h_index {
   class Solution {
   public:
     int hIndex(vector<int>& citations) {
-        sort(citations.begin(), citations.end());
-        int n = citations.size();
-        for (int i = 0; i < n; ++i) {
-            if (citations[i] >= n - i) {
-            return n - i;
-            }
+      sort(citations.begin(), citations.end());
+      int n = citations.size();
+      for (int i = 0; i < n; ++i) {
+        if (citations[i] >= n - i) {
+          return n - i;
         }
-        return 0;
+      }
+      return 0;
     }
   };
 }  // namespace h_index

include/leeter/product_of_array_except_self_238.hpp

@@ -0,0 +1,22 @@
+#include <vector>
+using std::vector;
+
+namespace product_of_array_except_self {
+  class Solution {
+  public:
+    vector<int> productExceptSelf(vector<int>& nums) {
+      int prefix_sum = 1;
+      int suffix_sum = 1;
+      vector<int> result(nums.size(), 1);
+      for (int i = 0; i < nums.size(); i++) {
+        result[i] = prefix_sum;
+        prefix_sum *= nums[i];
+      }
+      for (int i = nums.size() - 1; i >= 0; i--) {
+        result[i] *= suffix_sum;
+        suffix_sum *= nums[i];
+      }
+      return result;
+    }
+  };
+}  // namespace product_of_array_except_self

test/source/test_h_index_274.cpp

@@ -1,6 +1,6 @@
 #include <doctest/doctest.h>
-#include "leeter/h_index_274.hpp"
 
+#include "leeter/h_index_274.hpp"
 
 TEST_CASE("h index: test case 1") {
   vector<int> input = {3, 0, 6, 1, 5};

test/source/test_product_of_array_238.cpp

@@ -0,0 +1,17 @@
+#include <doctest/doctest.h>
+
+#include "leeter/product_of_array_except_self_238.hpp"
+
+TEST_CASE("Product of Array Except Self") {
+  product_of_array_except_self::Solution s;
+  std::vector<int> nums = {1, 2, 3, 4};
+  std::vector<int> expected = {24, 12, 8, 6};
+  CHECK(s.productExceptSelf(nums) == expected);
+}
+
+TEST_CASE("Product of Array Except Self - Test case 2") {
+  product_of_array_except_self::Solution s;
+  std::vector<int> nums = {-1, 1, 0, -3, 3};
+  std::vector<int> expected = {0, 0, 9, 0, 0};
+  CHECK(s.productExceptSelf(nums) == expected);
+}