c++ String searching goodness

[Treesin]

Hey guys, i've devised a cool way to search for a keyword in a string in C++. Just compile and run.

PHP Code:

#include <iostream>
#include <fstream>
#include <string>
#include <cassert>
#include <cstdio>

using namespace std;

int main(void)
{
 int a,i,z,loc,pos;
 string inputFileName;
 string s,term;
 ifstream fileIn;
 char ch;
 cout<<endl;
 cout<<endl;
 cout<<"Enter the name of a file of characters: ";
 cin>>inputFileName;
 cout<<endl;
 cout<<endl;
 fileIn.open(inputFileName.data());
 assert(fileIn.is_open() );
 i=0;
 while (!(fileIn.eof()))
  {ch=fileIn.get();
   s.insert(i,1,ch);     //insert character at position i
   i++;
  }
cout<<s;
cout<<endl;
cout<<endl;
cout<<"Enter a word/phrase you want to search for in the file you entered: ";
cin>>term;
cout<<"The word/phrase  *"<< term <<"*  will have '***' before it and after it"<<endl;
cout<<endl;
z = (int)term.length();

loc = 0;

while ((loc = s.find(term, loc)) != std::string::npos)
{
    // check for space at start of term, or check
    // for beginning of string
    if (loc != 0 && s[loc - 1] != ' ')
    {
        loc += z;
        continue;
    }

    // check for space at end of term, or check for end of string
    if (loc != (s.length() - z) && s[loc + z] != ' ')
    {
        loc += z;
        continue;
    }

    s.insert(loc, 1, '*');
    s.insert(loc+1, 1, '*');
    s.insert(loc+2, 1, '*');

    s.insert(loc+3+z, 1, '*');
    s.insert(loc+4+z, 1, '*');
    s.insert(loc+5+z, 1, '*');

    loc += z;
    loc += 6; // the amount of asterisks added
}
cout<<s;
 return 0;
} 


How about

Code:

#include <iostream>

#include <fstream>
#include <string>
#include <cstdio>

using namespace std;

string mark(string text,int startPos, int len){
    string toReturn = text;
    toReturn.insert(startPos,"***");
    toReturn.insert(startPos+len+3,"***");
    return toReturn;
}

int main(void){

    cout<<"~~~~~~~~~~~~~~"<< endl
        <<"Keyword Finder"<< endl
        <<"~~~~~~~~~~~~~~"<< endl;

    //Get user preferences
    string keyword = "ban";
    int lenKeyword;

   
    lenKeyword = keyword.size();
    string keywordPadded = " "+keyword+" ";
    
    //Read in data
    string fullText = "ban bananas, they are bannable when ban bands ban the bans ban";

    cout<<"File Text: "<< fullText << endl;
    cout<<fullText.size()<<endl;

    //iterate through each potential match and mark it
    for(int i = fullText.find(keywordPadded); i < fullText.size(); i = fullText.find(keywordPadded,i+lenKeyword)){
        cout << i << endl;
        fullText = mark(fullText,i+1,lenKeyword);
    }

    //check edge cases
    if(fullText.find(keyword+" ")==0)
        fullText = mark(fullText,0,lenKeyword);

    if(fullText.find(" "+keyword,fullText.size()-lenKeyword-1)==fullText.size()-lenKeyword-1)
        fullText = mark(fullText,fullText.size()-lenKeyword,lenKeyword);

    cout<<"Highlighted Text: "<< fullText << endl;
    return 0;
}

(Didn't fuck around with file I/O because I was using an online compiler, should be simple to implement though)