Write a program to calculate the number of seconds since midnight. for example, suppose the time is 1: 02: 05 am. since there are 3600 seconds per hour and 60 seconds per minutes, it has been 3725 seconds since midnight (3600 * 1 + 2 * 60 + 5 = 3725). the program asks the user to enter 4 pieces of information: hour, minute, second, and am/pm. the program will calculate and display the number of seconds since midnight. [hint: be very careful when the hour is 12].

// here is code in c++.

#include <bits/stdc++.h>

using namespace std;

int main()

{

   // variables

   int hour,min,sec,tot_sec;

   string str,s="AM";

   cout<<"enter number of hours:";

   // read hour

   cin>>hour;

   cout<<"enter number of minutes:";

   // read minute

   cin>>min;

   cout<<"enter number of seconds:";

   // read seconds

   cin>>sec;

   cout<<"Enter AM or PM:";

   // read AM or PM

   cin>>str;

   if((str.compare(s) == 0 )&& hour==12)

   {

       hour=0;

   }

   // calculate total seconds

   tot_sec=hour*3600+min*60+sec;

   // print the output

   cout<<"total seconds since midnight is : "<<tot_sec<<endl;

return 0;

}

Explanation:

Read the value of hour, minute, second and string "AM" or "PM" from user.

Then if string is equal to "AM" then make hour=0.Then multiply hour with

3600, minute with 60 and add them with second.It will give the total seconds

from midnight.

Output:

enter number of hours:12                                                                                                                                                

enter number of minutes:46                                                                                                                                              

enter number of seconds:23                                                                                                                                              

Enter AM or PM:AM                                                                                                                                            

total seconds since midnight is: 2783