update

codingStyleIdioms/3_RAII/c++_example1.cpp

@@ -0,0 +1,66 @@
+//
+// Created by light on 19-12-12.
+//
+#include <iostream>
+#include <vector>
+#include <cstring>
+#include <fstream>
+
+using namespace std;
+vector<string> read_lines_from_file(string &file_name) {
+    vector<string> lines;
+    string line;
+
+    ifstream file_handle (file_name.c_str());
+    while (file_handle.good() && !file_handle.eof()) {
+        getline(file_handle, line);
+        lines.push_back(line);
+    }
+
+    file_handle.close();
+
+    return lines;
+}
+vector<string> * read_lines_from_file1(string &file_name) {
+    vector<string> * lines;
+    string line;
+
+    ifstream file_handle (file_name.c_str());
+    while (file_handle.good() && !file_handle.eof()) {
+        getline(file_handle, line);
+        lines->push_back(line);
+    }
+
+    file_handle.close();
+
+    return lines;
+}
+vector<string> * read_lines_from_file1_1(string &file_name) {
+    vector<string> * lines=new vector<string>;
+    string line;
+
+    ifstream file_handle (file_name.c_str());
+    while (file_handle.good() && !file_handle.eof()) {
+        getline(file_handle, line);
+        lines->push_back(line);
+    }
+
+    file_handle.close();
+
+    return lines;
+}
+int main() {
+    // get file name from the first argument
+    string file_name ("/home/light/CLionProjects/Morden_C++/CMakeLists.txt");
+    int count = read_lines_from_file(file_name).size();
+    cout << "File " << file_name << " contains " << count << " lines.";
+
+    cout<<endl;
+//    string file_name1 ("/home/light/CLionProjects/Morden_C++/CMakeLists.txt");
+//    int count1 = read_lines_from_file1(file_name1)->size();
+//    cout << "File " << file_name << " contains " << count1 << " lines.";
+    string file_name1 ("/home/light/CLionProjects/Morden_C++/CMakeLists.txt");
+    int count1 = read_lines_from_file1_1(file_name1)->size();
+    cout << "File " << file_name << " contains " << count1 << " lines.";
+    return 0;
+}