#include <iostream>
#include <string>
#include <vector>
#include <cctype>
#include <algorithm>
 
int main()
{
	std::vector<std::string> Vec{ "A", "B", " ", "D", "E", " ", "", " " };
 
	// Helper function to see if string is all whitespace
	// Can also be implemented as free-function for readablity and
	// reusability of course
	auto stringIsWhitespace = [](const auto &str)
	{
		return std::all_of(
			begin(str), end(str), [](unsigned char c) { return std::isspace(c); });
	};
 
	// Find first non-whitespace from the back
	auto it = std::find_if(rbegin(Vec), rend(Vec), stringIsWhitespace);
	// Erase from there to the end
	Vec.erase(it.base(), end(Vec));
 
 
	for (auto const &str : Vec)
	{
		std::cout << "Element: " << str << std::endl;
	}
 
	return 0;
}

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