add: 220218 [C++]

2202/220218.cpp

@@ -0,0 +1,25 @@
+#include <string>
+#include <vector>
+#include <iostream>
+
+class Solution {
+public:
+	static std::string removeKdigits(const std::string& num, int k) {
+		std::vector<char> stack;
+		stack.reserve(num.length() - k);
+		for (char ch : num) {
+			while (k && !stack.empty() && stack.back() > ch) {
+				stack.pop_back();
+				--k;
+			}
+			stack.push_back(ch);
+		}
+		std::string ret(stack.begin(), k > 0 ? std::prev(stack.end(), k) : stack.end());
+		return ret.empty() || ret.find_first_not_of('0') == -1 ? "0" : ret.substr(ret.find_first_not_of('0'));
+	}
+};
+
+int main() {
+	std::cout << Solution::removeKdigits("1432219", 3);
+	return 0;
+}

2202/CMakeLists.txt

@@ -3,4 +3,4 @@ PROJECT(2202)
 
 SET(CMAKE_CXX_STANDARD 23)
 
-ADD_EXECUTABLE(2202 220218-CN.cpp)
+ADD_EXECUTABLE(2202 220218.cpp)