Make some changes

lib/utils.cpp

@@ -113,4 +113,47 @@ void print_sp_matrix_structure(const arma::sp_cx_mat &A)
     cout << endl;
 }
 
+std::vector<std::string> split(const std::string &s, char delim) {
+    std::vector<std::string> result;
+    std::stringstream ss(s);
+    std::string item;
+
+    while (getline(ss, item, delim)) {
+        result.push_back(trim(item));
+    }
+
+    return result;
+}
+
+inline std::string& ltrim(std::string& s, const char* t)
+{
+    s.erase(0, s.find_first_not_of(t));
+    return s;
+}
+
+inline std::string& rtrim(std::string& s, const char* t)
+{
+    s.erase(s.find_last_not_of(t) + 1);
+    return s;
+}
+
+inline std::string& trim(std::string& s, const char* t)
+{
+    return ltrim(rtrim(s, t), t);
+}
+
+inline std::string ltrim_copy(std::string s, const char* t)
+{
+    return ltrim(s, t);
+}
+
+inline std::string rtrim_copy(std::string s, const char* t)
+{
+    return rtrim(s, t);
+}
+
+inline std::string trim_copy(std::string s, const char* t)
+{
+    return trim(s, t);
+}
 } // namespace utils