erase

I have such code : vector <int> v; for (int i=0; i<5; i++) v.push_back(i); v.erase(find(v.rbegin(), v.rend(),2).base()); This code deletes the first element from vector v after first detected 2 (in vector remain: 0 1 2 4). What does .base() do here? base() converts a reverse iterator into the corresponding forward iterator. However, despite its simplicity, this correspondence is not as trivial as one might thing. When a reverse iterator points at one element, it dereferences the previous one, so the element it physically points to and the element it logically points to are different. In the

I'm reading data from 9 different sensors for my robot and I need to display them all steadily, in the same window so I can compare the values and see if any of the readings is off. The problem I'm having with both Serial.print and lcd.print is that the values are constantly moving and I can't really have a good look at them while moving the robot. I was thinking to call something like Serial.clear() before displaying anything else and that would just keep things steady and in one place, changing only the values. From what I found so far, Serial.print(17,BYTE) for instance is no longer

I have a map which elements are vectors.I have to delete from these vectors all elements which are equal to special number num std::map<size_t,std::vector<size_t> > myMap; for (std::map<size_t,std::vector<size_t> >::iterator itMap = myMap.begin();itMap != myMap.end();++itMap ) { for (std::vector<size_t>::iterator itVec = itMap->second.begin();itVec != itMap->second.end();) { auto itNextVec = itVec; ++itNextVec; if (*itVec == num) { itMap->second.erase(itVec ); } itVec = itNextVec; } } The code causes run-time exepssion .In VS - vector iterators incompatible . Can someone point what is the

I believe that since C++11, the erase function of most containers (e.g. std::vector ) accepts a const_iterator as parameter: iterator erase (const_iterator position); Still my compilers (GCC 4.8 and Clang 3.2, both using GCC libstdc++) won't allow me to use such function, even when compiling with --std=c++11 . Is it a compiler/libstdc++ bug, or did I do something bad? This is a sample code: #include <vector> int main( ) { std::vector<int> v; v.push_back( 1 ); v.push_back( 2 ); v.push_back( 3 ); std::vector<int>::const_iterator i = v.begin(); while( i != v.end() ) { i = v.erase( i ); } return 0

Is it possible with javascript? I'm trying to implement a scratchcard type thing, and I was wondering if the user could 'scratch it' with his cursor and then javascript would remove/erase the image to show the text below. But i've not been able to find anything (javascript wise) which can erase abit (cursor location) of an image. Does anyone have any suggestions/ideas? Thanks. Use html5 canvas element. Checkout this fiddle for an example: http://jsfiddle.net/ArtBIT/WUXDb/1/ jQuery Plugin: http://www.senamion.com/blog/jScratchcard.html HTML5: http://www.catchmyfame.com/2011/06/28/a-jquery

I have canvas. I have paint tools pencil and eraser. How i can erase drawings without overwrite(overdraw) with white color. this my code eraser over drawing with white color: http://jsfiddle.net/66z12xb0/ I have in back end save image after drawing. <?php $images = scandir(ROOT_FS . FINISH_DRAW_PATH, 1); $imageData = $GLOBALS['HTTP_RAW_POST_DATA']; $filteredData = substr($imageData, strpos($imageData, ",") + 1); $unencodedData = base64_decode($filteredData); $fileName = "photo.png"; $fp = fopen(ROOT_FS . SAVE_DRAW_PATH . $fileName, 'wb'); fwrite($fp, $unencodedData); fclose($fp); ?> Open with

How and why do 7- and 35-pass erases work? Shouldn't a simple rewrite with all zeroes be enough? I'd never heard of the 35-part erase: http://en.wikipedia.org/wiki/Gutmann_method The Gutmann method is an algorithm for securely erasing the contents of computer hard drives, such as files. Devised by Peter Gutmann and Colin Plumb, it does so by writing a series of 35 patterns over the region to be erased. The selection of patterns assumes that the user doesn't know the encoding mechanism used by the drive, and so includes patterns designed specifically for three different types of drives. A user