seg fault with simple function template

hey everyone,

Here's some code I wrote, and i was woundering why i was getting a segfault...

im just simply merging two vectors, with no repeats..

Code:

template <class T>
vector<T> merge(const vector<T> &c1, const vector<T> &c2) {

	vector<T> final;
	bool valid = true;

	for(typename vector<T>::const_iterator k = c1.begin(); k!=c1.end(); ++k) {
		final.push_back(*k);
	}
	
	for(typename vector<T>::const_iterator i = c2.begin(); i!=c2.end(); ++i) {
		for(typename vector<T>::const_iterator j = final.begin(); i!=final.end(); ++j) {
			if(*i==*j) {
				valid=false;
				break;
			}
		}
		if(valid)
			final.push_back(*i);

		valid=true;
	}

	return final;
}

Code:

int main(void) {
	
	vector<int> c1;
	vector<int> c2;

	c1.push_back(1);c1.push_back(2);c1.push_back(3);
	c2.push_back(1);c2.push_back(4);c1.push_back(5);
	
	vector<int> final = merge<int>(c1,c2);
	
	for (vector<int>::iterator i = final.begin(); i!=final.end(); ++i)
		cout << *i << endl;
	
	return 0;
}

This works fine for me on Windows with VC7:

Code:

#include <iostream>
#include <vector>

template <class T>
std::vector<T> merge(const std::vector<T> &c1, const std::vector<T> &c2) {

    std::vector<T> final;
    bool valid = true;

    for(typename std::vector<T>::const_iterator k = c1.begin(); k!=c1.end(); ++k) {
        final.push_back(*k);
    }

    for(typename std::vector<T>::const_iterator i = c2.begin(); i!=c2.end(); ++i) {
        for(typename std::vector<T>::const_iterator j = final.begin(); i!=final.end(); ++j) {
            if(*i==*j) {
                valid=false;
                break;
            }
        }
        if(valid)
            final.push_back(*i);

        valid=true;
    }

    return final;
}


int main(void) {

    std::vector<int> c1;
    std::vector<int> c2;

    c1.push_back(1);c1.push_back(2);c1.push_back(3);
    c2.push_back(1);c2.push_back(4);c1.push_back(5);

    std::vector<int> final = merge<int>(c1,c2);

    for (std::vector<int>::iterator i = final.begin(); i!=final.end(); ++i)
        std::cout << *i << std::endl;

    return 0;
}

hmmm thats very odd...its still giving me this error in g++

Code:

Segmentation fault (core dumped)

i had to re-write the function to make it work

the following works fine

Code:

template<class T>
vector<T> merge(const vector<T> &c1, const vector<T> &c2) {
	vector<T> final;

	copy(c1.begin(), c1.end(), back_inserter<vector<T > >(final));
	
	for(typename vector<T>::const_iterator i = c2.begin(); i!=c2.end(); ++i) {
		if(!binary_search(final.begin(),final.end(),*i))
			final.push_back(*i);
	}

	return final;		
}

Anyone got an suggestions on how to make my orignal code work on g++...?

The problem is that, in the inner loop, you are testing i!=final.end(). That test should be j!=final.end().

Incidentally (unrelated to the segmentation fault): if c1 includes duplicates, the end result of the merge function will still include those duplicates.