Text Rotation

[S_Grimm]

this was a project my teacher assigned to us a while ago. It's already been submitted, but im just looking to see if anyone has any optimization tips or see's anything i could have done better. Thanks in advance

c++:

/*  * Shane Grimminck  * Project 1  * Version 3.0 : Changed Compiler Warnings to level 4 and fixed possible loss of precision warnings  * 05/10/2011  */ #include <iostream> #include <fstream> #include <string> #include <locale> #include <map> #include <vector> #include <crtdbg.h> using namespace std; //static const locale created for the purpose of providing the encode method and the block of code used to check for one letter words to check to see if the word is an alphabetic character static const locale here (""); //Function Encode //Purpose is to encode the character passed in, using the cipher key and the jump table //accepts a character, the cipher key and the 52 element jump table char encode (char& ch, int const& cipherKey, vector<char>& jumptable) {         //if its a character rotate it         if (isalpha(ch, here))         {                 if ( ch >= 'a')                         return jumptable[ch - 71];                 else                         return jumptable [ch-65];         }         //if its not a character put it back in.         else         {                 return ch;         } } int main(int argc, char *argv[]) {         //debug memory leak checks         #if defined(_DEBUG)         int dbgFlags = ::_CrtSetDbgFlag(_CRTDBG_REPORT_FLAG);         dbgFlags |= _CRTDBG_CHECK_ALWAYS_DF; //check block integrity on every memory call         dbgFlags |= _CRTDBG_DELAY_FREE_MEM_DF; // dont remove blocks on delete         dbgFlags |= _CRTDBG_LEAK_CHECK_DF; //check for memory leaks at process termination         _CrtSetDbgFlag( dbgFlags );         #endif         //create a vector to hold the 52 alphabetic characters and populate it         vector<char> jumptable;         for (int i = 'A'; i <= 'Z'; ++i)         {                 jumptable.push_back(static_cast<char>(i));         }         for (int i = 'a'; i <= 'z'; ++i)         {                 jumptable.push_back(static_cast<char>(i));         }         // parse the command line arguments and store them in a vector for use later         vector<string> args;         for( int i = 0; i < argc; ++i )         {                 args.push_back( argv[i] );         }         //check to make sure we have recieved the correct number of arguments. If not exit the program         if (argc != 4)         {                 cout << "Invalid Number of parameters. " << endl << "Input paramaters are [input file name] [cipher letter] [output file name]" << endl;                 return EXIT_FAILURE;         }         //try to open the input file. If it cant be opened, exit the program         ifstream inputFile (args[1]);         if (!inputFile)         {                 cout << "File " << args[1] << " could not be opened for reading" << endl;                 return EXIT_FAILURE;         }         string currentWord; //current word we are working on         map<string, int> singleLetter; //map to hold the one letter words we find         while( inputFile >> currentWord)         {                 if(currentWord.length() == 1 && isalpha(currentWord[0], here )) //if the word length is 1 and it is a alphabetic character put it into the map                 {                         ++singleLetter[currentWord];                 }         }         //figure out what number occurs is the highest in the map, its corresponding string element is the most common one letter word.         //Put that word into currentWord to save on memory, by not using another string         int freqOcc = 0;         for (map<string, int>::iterator it=singleLetter.begin(); it!=singleLetter.end(); ++it)         {                 if (it->second > freqOcc)                 {                         currentWord = it->first;                         freqOcc = it->second;                 }         }         //output the results         cout << "Most frequent letter : " << currentWord << " occurs " << freqOcc << " times." << endl;         //find the cipher key and output the results         int n1 = 0, n2 = 0;         for (unsigned i = 0; i < jumptable.size(); ++ i)         {                 if (currentWord[0] == jumptable[i])                         n1 = i;                 if (args[2][0] == jumptable[i])                         n2 = i;         }         int const& cipherKey = n2 - n1;         cout << "Cipher Key is : " << cipherKey << endl;                 vector<char> rotatedTable;                 for (int i = 'A'; i <= 'Z'; ++i)         {                 if(cipherKey >= 0)                         rotatedTable.push_back(jumptable[((((i - 65) + cipherKey) % 52) )]);                 else                         rotatedTable.push_back(jumptable[((((i - 65) +( cipherKey+ 52)) % 52))]);         }         for (int i = 'a'; i <= 'z'; ++i)         {                 if(cipherKey >= 0)                         rotatedTable.push_back(jumptable[((((i - 71) + cipherKey) % 52) )]);                 else                         rotatedTable.push_back(jumptable[((((i - 71) +( cipherKey+ 52)) % 52))]);         }         //open the output file, exit if it cant be opened         ofstream outputFile (args[3]);         if (!outputFile.is_open())         {                 cout << "Unable to open or create " << args[3] << endl;                 return EXIT_FAILURE;         }         //clear the EOF from inputFile and set the seek position to 0 (start of the file)         inputFile.clear();         inputFile.seekg(0);         //read in a character at a time and output the character after encoding. Calls the encode function.         char originalValue;         while(inputFile.get(originalValue))         {                 outputFile.put(encode(originalValue, cipherKey, rotatedTable));         }         //before end of the file, close files         if (inputFile.is_open())                 inputFile.close();         if (outputFile.is_open())                 outputFile.close(); }

Visual Studio 2010 used.
//Program Purpose is to read a text file and encode or decode it based on the most common one letter word (english language has 4: I, A, a, and O)
//Encoding is done by rotating the alphabetic characters by the offset determined by taking the users input and the most frequent one letter word.
//Originally used with an encoded book, Dracula.