C/C++ :: Dictionary Logic - Searching For More Words?

I need to create code based upon the following pseudo code:

dictionary=vector
file containing words to search for=external file

While there more words to search, for search the dictionary if the entire dictionary is searched and the word is not found, return the word, search the dictionary for the next element (and so on)

I cannot for the life of me figure out the sequence of loops to do this. The following code returns all of the words instead of just the ones not found in the dictionary, but it's all I've got after countless changes:

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
using namespace std;
int main() {
string dictword;
ifstream dictionary;

[Code] ....

And it returns every word in the external file.