vector 删除指定元素

用到了 remove_if 和 lambda 函数

#include <iostream>
#include <vector>
#include <algorithm>
int main() {
	std::vector<int> v(10, 1);
	std::cout << "size:" << v.size() << std::endl;
	v[4] = -1;
	v.erase(std::remove_if(v.begin(), v.end(),
		[](int x) {return x == -1; })); // 删除 -1 
	for (int i : v) {
		std::cout << i << std::endl;
	}
	std::cout << "size:" << v.size() << std::endl;
    return 0;
}