What errors did it give you?
ETA: After fixing a few warnings related to the comparison of unsigned/signed and reusing counter variables in your for(;;) constructs, it compiled, ran and seemed to at least work without crashing. This is not to say that it necessarily generates the results you expect, but hopefully this is a stepping-off point for you.
To fix the counter variable problem, change this:
Code:
string swapLetters(string NodeData,int lettertoswap)
{
string output="";
int len=NodeData.length();
for(int i=0;i<lettertoswap;i++)
output=output+NodeData[i];
output=output+NodeData[i+1];
output=output+NodeData[i];
for( i=lettertoswap+2;i<len;i++)
output=output+NodeData[i];
return output;
}
to this:
Code:
string swapLetters(string NodeData,int lettertoswap)
{
string output="";
int len=NodeData.length();
int i = 0;
for(i=0;i<lettertoswap;i++)
output=output+NodeData[i];
output=output+NodeData[i+1];
output=output+NodeData[i];
for( i=lettertoswap+2;i<len;i++)
output=output+NodeData[i];
return output;
}