Program to calculate difference between two times for "time travel" - c++

Question

I am writing a "time travel" program which is supposed to ask the user for the current time, their target travel time, relay those values to be converted into minutes in a function and then based on if the time difference is too high it will not allow the time travel or if it is allowed it will print if they are in the future or the past. My issue right now is that the current time, which is only supposed to be relevant the first iteration, or the first "jump" of the program is not being updated after the jump occurs, and the program defaults to it instead of the target time, which is supposed to be the technical "current time" after the jump has occurred. I have been trying to figure this out for hours and I can't, so I am hoping someone could help me out.
Thank you for your time
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;
int compute_time_difference(int c_hrs, int c_mins, bool c_am, int t_hrs, int t_mins, bool t_am);
void print_future();
void print_past();
void print_SecurityProtocol();
int main()
{
int c_hrs, c_mins;
int t_hrs, t_mins;
int system_time2;
int time_difference2;
bool c_am = 0;
bool t_am = 0;
char c, c2, Y, N, y, n, jumpAgain;
string am_or_pm_current, am_or_pm_target;
bool g_stop = true;
cout << "Welcome to Po Sled" << endl;
cout << "\tSystem booting..." << endl;
for (int i = 0; i<1; i++) //for loop to run once
{
cout << "\n\tEnter current time below: " << endl;
cout << "\t>Enter hour: "; //User inputs current time in hours
cin >> c_hrs;
while (c_hrs > 12 || c_hrs < 1)
{
cout << "Error: Please enter an hour in the range [1, 12]: ";
cin >> c_hrs;
}
cout << "\t>Enter minutes: "; //User inputs current time in minutes
cin >> c_mins;
while (c_mins > 59 || c_mins < 0) {
cout << "Error: Please enter minutes in the range [0, 59]: ";
cin >> c_mins;
}
cout << "\t>Is it AM or PM?: "; //Classifying if current time is AM or PM
cin >> am_or_pm_current;
while (am_or_pm_current != "am" && am_or_pm_current != "AM" && am_or_pm_current != "pm" && am_or_pm_current != "PM") { //Checks if valid input, if not repeats message until valid
cout << "\tError: Please enter AM/am or PM/pm: ";
cin >> am_or_pm_current;
}
if ((am_or_pm_current == "am") || (am_or_pm_current == "AM"))
{
c_am = 1;
}
else if ((am_or_pm_current == "pm") || (am_or_pm_current == "PM"))
{
c_am = 0;
}
cout << "\n\tCurrent system time set to " << c_hrs << ":" << setw(2) << setfill('0') << c_mins << am_or_pm_current << endl;
cout << "\n\t\tIs this time correct (Y or N)? ";
cin >> c;
while (c != 'Y' && c != 'y' && c != 'n' && c != 'N')
{
cout << "\t\t\tError: Please enter Y/y or N/n: ";
cin >> c;
}
if (c == 'N' || c == 'n')
{
continue;
}
else
{
cout << "\n\tSystem initializing and TARDIS unit warming...." << endl;
cout << "\tThe Po Sled is engaged and ready for input." << endl;
}
}
do {
//Starts a loop for target jump
cout << "\n\tEnter target time below: " << endl; //Enters target time of jump
cout << "\t>Enter Hour: ";
cin >> t_hrs;
while (t_hrs > 12 || t_hrs < 1) {
cout << "Error: Please enter an hour in the range [1, 12]: ";
cin >> t_hrs;
}
cout << "\t>Enter minutes: ";
cin >> t_mins;
while (t_mins > 59 || t_mins < 0) {
cout << "\tError: Please enter minutes in the range [0, 59]: ";
cin >> t_mins;
}
cout << "\n\tIs it AM or PM?: ";
cin >> am_or_pm_target; //Classifying if target time is AM or PM
while (am_or_pm_current != "am" && am_or_pm_current != "AM" && am_or_pm_current != "pm" && am_or_pm_current != "PM")
{ //Validates input is AM or PM
cout << "\tError: Please enter AM/am or PM/pm: ";
cin >> am_or_pm_target;
}
if ((am_or_pm_target == "am") || (am_or_pm_target == "AM"))
{
t_am = 1;
}
else if ((am_or_pm_target == "pm") || (am_or_pm_target == "PM"))
{
t_am = 0;
}
cout << "\tTarget time set to " << t_hrs << ":" << setw(2) << setfill('0') << t_mins << am_or_pm_target; //Sets target time
cout << "\n\t\tIs this time correct (Y or N)? "; //Validates if target time entered is correct
cin >> c2;
while (c2 != 'Y' && c2 != 'y' && c2 != 'n' && c2 != 'N')
{
cout << "\t\t\tError: Please enter Y/y or N/n: ";
cin >> c2;
}
time_difference2 = compute_time_difference(c_hrs, c_mins, c_am, t_hrs, t_mins, t_am);
if (time_difference2 > 360) //If time difference is greater than 6 hours prints error function
{
print_SecurityProtocol();
continue;
}
if (c2 == 'N' || c2 == 'n')
{
continue;
}
cout << "\tJump was made, the current time is " << t_hrs << ":" << setw(2) << setfill('0') << t_mins << am_or_pm_target << endl;
if (time_difference2 < 0 && time_difference2 > -360) //If time difference is less than 0 prints past function
{
print_past();
}
else if (time_difference2 >= 0 && time_difference2 <= 360) //If time difference is ahead of current time prints future function
{
print_future();
}
cout << "\tWould you like to jump again (Y/N)? ";
cin >> jumpAgain;
while (jumpAgain != 'Y' && jumpAgain != 'y' && jumpAgain != 'n' && jumpAgain != 'N') //Input validation
{
cout << "\t\t\tError: Please enter Y/y or N/n: ";
cin >> jumpAgain;
}
if (jumpAgain == 'n' || jumpAgain == 'N') //User exiting program
{
if (time_difference2 < 0)
{
cout << "\t\tSystem shutting down; enjoy the past.\n" << endl;
}
else if (time_difference2 >= 0 && time_difference2 < 360)
{
cout << "\t\tSystem shutting down; enjoy the future.\n" << endl;
}
}
if (jumpAgain == 'Y' || jumpAgain == 'y')
{
continue;
}
} while (jumpAgain != 'n' && jumpAgain != 'N');
return 0;
}
int compute_time_difference(int c_hrs, int c_mins, bool c_am, int t_hrs, int t_mins, bool t_am) //Computes time differences.
{
int currentTime_hours, currentTime_minutes, targetTime_hours, targetTime_minutes, currentTime, targetTime;
int time_difference;
if (c_am == 1) //if c_am is true and it is morning
{
if (c_hrs == 12)
{
currentTime_hours = c_hrs * 0;
}
else if (c_hrs != 12)
{
currentTime_hours = (c_hrs * 60);
currentTime_minutes = c_mins;
currentTime = currentTime_hours + currentTime_minutes; //Sets the value of the current time
}
}
else if (c_am == 0) //if c_am is false and it is afternoon time
{
if (currentTime_hours == 12)
{
c_hrs = c_hrs * 60;
}
else if (currentTime_hours != 12)
{
currentTime_hours = ((c_hrs + 12) * 60);
currentTime_minutes = c_mins;
currentTime = currentTime_hours + currentTime_minutes; //Sets the value of the current time
}
}
if (t_am == 1) //if t_am is true and it is morning time
{
if (targetTime_hours == 12) //if target hours equal to 12 special math
{
targetTime_hours = t_hrs*0;
}
else if (targetTime_hours != 12) //else do this math
{
targetTime_hours = ((t_hrs) * 60);
targetTime_minutes = t_mins;
targetTime = targetTime_hours + targetTime_minutes;
}
}
else if (t_am == 0) //if target time equal to pm then do this math
{
if (targetTime_hours == 12)
{
targetTime_hours = t_hrs * 60;
}
else if (targetTime_hours != 12) //else if target time not equal to 12 then do normal pm math
{
targetTime_hours = ((t_hrs + 12) * 60);
targetTime_minutes = t_mins;
targetTime = targetTime_hours + targetTime_minutes;
}
}
time_difference = targetTime - currentTime;
cout << "the difference computed is " << time_difference;
return time_difference;
}
void print_SecurityProtocol() //Function which prints security protocol error message
{
cout << "\tSecurity Protocols Engaging" << endl;
cout << "\t\tError: The time difference is greater than 6 hours." << endl;
cout << "\t\t\tPlease re-enter target time." << endl;
}
void print_past() //Function that prints when a user is in the past
{
cout << "\tHold onto your lower posterior regions" << endl;
cout << "\n\t\tYou are now in the relative past" << endl;
}
void print_future() //Function that prints when a user is in the future
{
cout << "\tHold onto your lower posterior regions" << endl;
cout << "\n\t\tYou are now in the relative future " << endl;
}

Answer 1

Why do you not use a system time call, instead of getting user input for the 'current time'? Also, use a 24-hour clock instead of a 12-hour and you have removed the need to cater for am/pm within your process.
AM n ot much of a coder but c_hrs*60 would be (at least) 60 hours and (at most) 24*60 which, with the exception of a drive across Europe, Russia, Australia or the Northern US would be excessive time recording. Do you not mean to refer to MINUTES instead of hours (c_mins*60)?