Istringstreams and string manipulation.

Hello,

My main problem currently is what to do exactly for this program. I have no idea on where to go or what to add or change. I am trying to read information from a file, and then change the format of the information. For example, I need to change the name format to have the middle name have just the first letter and a period. Such as "Chris Jones Johnson" to become "Johnson, Chris J." I also need to format time given as "10:10 PM" to military time. I also need to encrypt a message from the file. Here is the code I have so far. Please tell me what I need to delete or add or change.

Thank you in advance,
Roy

Code:

#include <iostream>
#include <cstdlib>
#include <fstream>
#include <string>
#include <sstream>
#include <vector>
#include <iomanip>
using namespace std;

string mtime(string time, ofstream &date);

int main() {
    ifstream blog;
    ofstream outblog;
    char file[30];
    char o, e, i;
    int key, b;
    string originalChar, echar, tempchar    ;
    istringstream Name, Date, Code;                //Used to sort data from the file
    string fname, lname, mname, time, name[3];
    cout << "Please enter the name of a blog file:" << endl;
    cin >> file;
    cout << "Please enter an encryption key between 1 and 100" << endl;        //Used to encrypt the file
    cin >> key;
    if (key < 1 || key > 100) {
        cout << "The key entered was not between 1 and 100" << endl;        //Makes sure the user inputs within the range
        return 0;
        exit(0);
    }
    blog.open("file");
    if (blog.fail()) {            //Makes sure the file was opened sucessfully
        perror("blog");
        exit(0);
    }
    getline(blog, name[3]);    
    Name.str(name[3]);
    while (Name >> name[3]) {            //Supposed to read data into the given variables.
        Name >> fname >> mname >> lname;
        mname.substr(0, 2);
        mname.insert(1, ".");
    
    }
    getline(blog, time);
    Date.str(time);
    while (Date >> time)    {
        Date >> time;
        b = time.find(":");
        time.erase(b, 1);        
        time.insert(b, " ");
    }
    getline(blog, originalChar);
    Code.str(originalChar);
    Code >> originalChar;

    for (i = 0; i < originalChar.length(); i++) {
        tempchar = originalChar;
    if (originalChar.at(i) + key > 126) {        //Encrypts the message from the blog file.
        originalChar.at(i) = 32 + ((o + key ) - 127);
    }
    else {
        originalChar.at(i) = (o + key);
        
    } 
    }
    echar = originalChar;
    cout << echar << endl;
    mtime;
}

string mtime(string time, ofstream &date) {    //Switches around the time format to military time
    while (date << time) {
        int b, hours, minutes;                        
        string Day;
        b = mtime.find(":");
        mtime.erase(b, 1);        
        mtime.insert(" ");        
        mtime >> hours >> minutes >> "hours";
        
        if (time.find("PM")) {
            hours = hours + 12;
        }
        istringstream ntime;
        date << setw(2) << hours << minutes << Day;
        cout << date;
    }
}]

First try to implement everything as best as you can. Once you get stuck somewhere at that point then post here for advice. Beyond that, I would say put everything into functions; modular code is much easier to understand and maintain. Also, NEVER use the "exit" function in a C++ program; it undermines the proper destruction of objects. Instead, just throw an exception; if it get's caught somewhere up the line, fine. Otherwise, the program will just terminate BUT your destructors will still be invoked properly, so all will be well.

Good luck!