Why is Vector Iterator not dereferencable?

Question

Getting vector iterator not deferencable for code below, but I don't see why. I am simply iterating through the 2d array and instantiating all values to 0. Where am I iterating to an invalid location?

vector<vector<bool>> isduplicate(100);

        for(int i=0;i<isduplicate.size();i++){
            for(int s=0;s<isduplicate.size();s++)
            isduplicate[i][s]=false;
        }

Answer 1

You are iterating over isduplicate twice. You should iterate over isduplicate[i] in the inner loop:

vector<vector<bool>> isduplicate(100);
for(int i=0;i<isduplicate.size();i++){
    for(int s=0;s<isduplicate[i].size();s++)
       isduplicate[i][s]=false;
} 

However, isduplicate[i] is empty for all i , therefore you won't iterate over anything in the inner loop.

If what you want is to have 100 vectors of 100 bool s containing the false value, then:

vector<vector<bool>> isduplicate(100, vector<bool>(100, false));

Should do it.