Excel sheet column title (#199)

* add excel sheet column title

* impl excel sheet column title

leetcode-cc/ExcelSheetColTitle.hpp

@@ -0,0 +1,41 @@
+#include "TestHelper.h"
+#include "problem.h"
+#include "solution.h"
+
+using namespace std;
+
+IMPLEMENT_PROBLEM_CLASS(
+    PExcelSheetColTitle, 168, DIFFI_EASY, TOPIC_ALGORITHMS,
+    "Excel Sheet Column Title",
+    "Given an integer columnNumber, return its corresponding column title as "
+    "it appears in an Excel sheet.",
+    {"Math"});
+
+class SExcelSheetColTitle : public ISolution {
+ public:
+  size_t problemId() const override { return 168; }
+  string name() const override {
+    return ("Solution for " + string("Excel Sheet Column Title"));
+  }
+  string location() const override { return __FILE_NAME__; }
+  int test() const override {
+    return testHelper<int, string>(
+        {1, 28, 701}, {"A", "AB", "ZY"},
+        [this](auto input) { return this->convertToTitle(input); });
+  };
+  int benchmark() const override { return 0; }
+
+ private:
+  string convertToTitle(int columnNumber) const {
+    string res = "";
+
+    while (columnNumber) {
+      columnNumber--;
+      int mod = columnNumber % 26;
+      res = char('A' + mod) + res;
+      columnNumber /= 26;
+    }
+
+    return res;
+  }
+};

runtime-cc/src/registration.cc

@@ -22,6 +22,7 @@
 #include "../leetcode-cc/DistinctSubsequences.hpp"
 #include "../leetcode-cc/DivideTwoIntegers.hpp"
 #include "../leetcode-cc/EvaluateReversePolishNotation.hpp"
+#include "../leetcode-cc/ExcelSheetColTitle.hpp"
 #include "../leetcode-cc/FindMinInRotatedSortedArray.hpp"
 #include "../leetcode-cc/FindMinInRotatedSortedArrayII.hpp"
 #include "../leetcode-cc/FindPeakElement.hpp"
@@ -725,5 +726,10 @@ const int registerAll(std::shared_ptr<Container> handle) {
     return std::make_shared<STwoSumIIInputArraySorted>();
   });
 
+  handle->registerProblem(
+      []() -> ArcProblem { return std::make_shared<PExcelSheetColTitle>(); });
+  handle->registerSolution(
+      []() -> ArcSolution { return std::make_shared<SExcelSheetColTitle>(); });
+
   return 0;
 }