Create for_each.cpp

Algorithm_header/for_each.cpp

@@ -0,0 +1,43 @@
+#include <iostream>   // std::cout
+#include <vector>     // std::vector
+
+template <class InputIt, class UnaryFunction>
+constexpr UnaryFunction for_each(InputIt first, InputIt last, UnaryFunction f) {
+	for (; first != last; ++first) {
+		f(*first);
+	}
+	return f;
+}
+
+void myfunction(int i) {  // function:
+	std::cout << ' ' << i;
+}
+
+struct myclass {  // function object type:
+	void operator()(int i) { std::cout << ' ' << i; }
+} myobject;
+
+int main() {
+	std::vector<int> myvector;
+	myvector.push_back(10);
+	myvector.push_back(20);
+	myvector.push_back(30);
+
+	// Passing general function pointers
+	std::cout << "myvector contains:";
+	for_each(myvector.begin(), myvector.end(), myfunction);
+	std::cout << '\n';
+
+	// pass the Functor
+	std::cout << "myvector contains:";
+	for_each(myvector.begin(), myvector.end(), myobject);
+	std::cout << '\n';
+
+	// Pass the lambda function
+	std::cout << "myvector contains:";
+	for_each(myvector.begin(), myvector.end(),
+		[](const int& n) { std::cout << ' ' << n; });
+	std::cout << '\n';
+
+	return 0;
+}