Fix indentation, compilation about trivial missing include, add tests.

leetcode/523.cpp

@@ -1,32 +1,46 @@
-/*
-    Given an integer array and an integer k, return true if the arary has a
-    (continuous) subarray with length at least two whose elements of the subarray
-    is a multiple of k.
-  */
+#include <vector>
 
-  bool checkSubarraySum(vector<int>& nums, int k) {
-      const int n = static_cast<int>(nums.size());
-      if (n < 2) return false;
-      int i = 0, j = 1;
-      unsigned sum = 0;
-      while (i < n) {
-          sum += nums[i];
-          while (j < n) {
-              sum += nums[j];
-              if (!(sum % k)) return true;
-              j ++;
-          }
-          j--;
-          sum -= nums[i];
-          i++;
-          if (i == n) break;
-          while (j >= i + 1) {
-              if (!(sum % k)) return true;
-              sum -= nums[j];
-              j--;
-          }
-          sum -= nums[i];
-          i++, j +=2;
-      }
-      return false;
-  }
+#include <gtest/gtest.h>
+
+// Check if the arary has a (continuous) subarray of at least
+// two elements whose sum is a multiple of k.
+bool check_subarray_sum(const std::vector<int>& nums, int k)
+{
+    const int n = static_cast<int>(nums.size());
+    if (n < 2) return false;
+    int i = 0, j = 1;
+    unsigned sum = 0;
+    while (i < n) {
+        sum += nums[i];
+        while (j < n) {
+            sum += nums[j];
+            if (!(sum % k)) return true;
+            j ++;
+        }
+        j--;
+        sum -= nums[i];
+        i++;
+        if (i == n) break;
+        while (j >= i + 1) {
+            if (!(sum % k)) return true;
+            sum -= nums[j];
+            j--;
+        }
+        sum -= nums[i];
+        i++, j +=2;
+    }
+    return false;
+}
+
+TEST(CheckSubarraySumDivisibility, a)
+{
+    const std::vector nums{23, 2, 6, 4, 7};
+    EXPECT_EQ(check_subarray_sum(nums,  6), true);
+    EXPECT_EQ(check_subarray_sum(nums, 13), false);
+}
+
+int main(int argc, char **argv)
+{
+    testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}