Contours / Connected components in OpenCV 2.4.4 - c++

Question

I'm currently working on an image with a lot of detected contours.
My goal is to narrow down the number of contours to end up with only the one I'm looking for.
For that I conduct a bunch of tests based on area and bounding box.
For now I do after every step a drawContours for the contours that I want to keep followed by a findContours.
My problem is that I would like to do findContours only once and then just erase the contours I don't want, is this possible?
Current way :
Mat src;
Mat BW;
src = imread("img.bmp", 0);
if( src.channels() > 1)
{
cvtColor(src, src, CV_BGR2GRAY);
}
threshold(src, BW, 100, 255, CV_THRESH_OTSU);
imshow( "Tresh", BW );
Mat dst = Mat::zeros(src.rows, src.cols, CV_8UC3);
Mat dstP = Mat::zeros(src.rows, src.cols, CV_8UC3);
Mat dst1 = Mat::zeros(src.rows, src.cols, CV_8UC3);
Mat dst2 = Mat::zeros(src.rows, src.cols, CV_8UC3);
vector<vector<Point> > contours;
vector<Vec4i> hierarchy;
findContours( BW, contours, hierarchy, CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE );
for( int i = 0; i < contours.size(); i++ )
{
Scalar color( rand()&255, rand()&255, rand()&255 );
drawContours( dst, contours, i, color, 2/*CV_FILLED*/, 8, hierarchy );
}
/// Test on area ******************************************************************
for( int i = 0; i < contours.size(); i++ )
{
if ( contourArea(contours[i], false) > 100 && contourArea(contours[i], false) < 200000)
{
Scalar color( rand()&255, rand()&255, rand()&255 );
drawContours( dst1, contours, i, color, CV_FILLED, 8, hierarchy );
}
}
/// Next test **********************************************************************
cvtColor(dst1, dstP, CV_BGR2GRAY);
findContours( dstP, contours, hierarchy, CV_RETR_CCOMP, CV_CHAIN_APPROX_SIMPLE );
etc
Wanted way :
if ( contourArea(contours[i], false) < 100 && contourArea(contours[i], false) > 200000)
{
contours.erase(i); // Doesn't work
}
Does anyone now how to erase those contours?
PS : I don't care about inner contours, I want all of them to go trough my tests.
EDIT, the solution (pointed out by limonana) is : contours.erase(contours.begin()+i);