Thread: please help!...find and replace

Hi!
I'm doing a basic course at uni and i have an assignment where i have to prompt the user for a file name; find if the file exists, and then propt the user for a word to find in the file, and then a word to replace in the file. I then have to replace the word and output this to a new file.
This is what i have done so far, but im unsure of how to do the find and replace stuff!
All help would be very much appreciated; here's what ive done so far..also i cant use <string> cos i havent covered in class, i can only use <cstring>.

Here's my code:

Code:

#include<iostream>
#include<fstream>
#include<cstring>
using namespace std;

int main()

{

           char file[50];
           char string_find [50];
           char string_replace[50];
          
           cout << "Enter an input file: " << endl;
           cin >> file;

           ifstream infile;
           infile.open(file);

           if(infile.fail())
                 cout << "File could not be opened" << endl;
           else 
            {
                  cout << "Enter a string to find: " << endl;
                  cin >> string_find;

                  cout << "Enter a string to replace with: " << andl;
                  cin >> string_replace;

                  ofstream outfile;
                  outfile.open(strcat(file,".out"));
                  outfile << "test";
               }
               
               return 0;
}

Your help is very much appreciated! Thanks in advamce, amy