rainbow.cpp

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

int main(int argc, char **argv)
{
   int i = 0;
   int color[] = {31, 33, 32, 34, 35};
   char fileName[256];
   char letter;
   
   if (argc < 2)
   {   
      cout << "File Name? ";
      cin.getline(fileName, 256);
   }
   else
      strcpy(fileName, argv[1]);
   ifstream fin;
   fin.open(fileName);
   if (fin.fail())
   {
      cout << "ERROR: " << fileName << " does not exist\n";
      return 1;
   }
   i = 0;
   for (int c = 0; ! fin.eof(); i++)
      {
         if (c > 4)
         c = 0;
         fin.get(letter);
         cout << "\E[1;" << color[c] << "m";
         cout << letter;
         if (letter != ' ')
         c++;
      }
   cout << "\E[0m";
   return 0;
}