class TraceLifetime {
public:

    TraceLifetime(const char* variable_name);              // Create and print message.
    ~TraceLifetime();                                      // Destroy and print message.
private:
    enum { max_objects_to_trace = 100 };                   // Maximum number of objects to trace
    static char existing_objects[1+max_objects_to_trace];  // L = live; D = destroyed.
    static int total_created;
    int instance_number;                                   // Creation sequence number.
    char var_name[21];                                     // Name of variable (first 20 chars + null)
    // This should be String, but I get an internal compiler error message when using String

};

#include <string.h>
#include <iostream.h>


int  TraceLifetime::total_created = 0;
char TraceLifetime::existing_objects[1+TraceLifetime::max_objects_to_trace] = "";


TraceLifetime::TraceLifetime(const char* variable_name) : 
    instance_number(total_created++) {
    // Copy first 20 characters of variable name
    strncpy(var_name, variable_name, 20);
    var_name[20] = '\0';

    if (total_created <= max_objects_to_trace) {

        existing_objects[total_created-1] = 'L';
        existing_objects[total_created]   = '\0';

        cout << existing_objects << " TraceLifetime constructed for " << var_name << "." << endl;
    }
}
 
TraceLifetime::~TraceLifetime() {
    if (instance_number < max_objects_to_trace) {
        existing_objects[instance_number] = 'D';
        cout << existing_objects << " TraceLifetime destroyed for " << var_name << "." << endl;
    }
}

//main routines start here
void f2() {
    cout << "-- f2 starts -- " << endl;
    TraceLifetime c("c");
    throw "exception";
    cout << "-- f2 ends -- " << endl;
}

void f1() {
    cout << "-- f1 starts -- " << endl;
    TraceLifetime a("a");
    f2();
    TraceLifetime b("b");
    cout << "-- f1 ends -- " << endl;
}

int main() {
    cout << "-- main starts --" << endl;
    try { 
        f1();
    }
    catch(const char* dd) {
      cout << "Exception caught." <<dd<< endl;
    }
    cout << "-- main ends --" << endl;
    return 0;
}