C/C++ :: How To Swap First And Last Letters Of Input Stream

I simply need to know how I could swap the first and last letters of the input in this program:

int main() {
    cout << "---------------------------------------------------------" << endl;
    cout << "              Letter Swapping Program" << endl;
    cout << "---------------------------------------------------------" << endl;  
    string word;
    cout << "Please enter a word at least 3 letters long: ";
    cin >> word;

[Code] ....

By all means, I know this is a messy program and is not the most concise way to write it....