add: 220417-CN [cpp]

cpp/2204/220417-CN.cpp

@@ -0,0 +1,29 @@
+#include <string>
+#include <vector>
+#include <cctype>
+#include <iostream>
+#include <algorithm>
+#include <unordered_map>
+
+class Solution {
+public:
+	static std::string mostCommonWord(std::string paragraph, const std::vector<std::string>& banned) {
+		std::unordered_map<std::string, int> freq;
+		std::for_each(paragraph.begin(), paragraph.end(), [](char& c){ c = std::tolower(c); });
+		paragraph.push_back('.');
+		const char* ptr = paragraph.c_str();
+		for (const char* p1 = ptr, * p2 = ptr; *p2; ++p2) {
+			if (!std::isalpha(*p2)) {
+				if (p2 - p1)
+					++freq[std::string(p1, p2)];
+				p1 = 1 + p2;
+			}
+		}
+		std::for_each(banned.cbegin(), banned.cend(), [&freq](const std::string& str) { freq.erase(str); });
+		return std::max_element(freq.cbegin(), freq.cend(), [](const std::pair<std::string, int>& x, const std::pair<std::string, int>& y) { return x.second < y.second; })->first;
+	}
+};
+
+int main() {
+	std::cout << Solution::mostCommonWord("Bob hit a ball, the hit BALL flew far after it was hit.", {"hit"});
+}

cpp/2204/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2204)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2204 220417.cpp)
+ADD_EXECUTABLE(2204 220417-CN.cpp)