vector删除的简洁写法

#include <iostream>
#include <vector>
#include <algorithm>
struct Test
{
  int a;
  int b;
  Test(int _a, int _b) { a = _a; b = _b; }
};
bool Is_2(Test t) { return (2 == t.a); }
int main()
{
  std::vector<Test> vec;
  Test t1(1, 1);
  Test t2(2, 2);
  Test t3(3, 3);
  Test t4(4, 4);
  Test t5(5, 5);
  vec.push_back(t1);
  vec.push_back(t2);
  vec.push_back(t3);
  vec.push_back(t4);
  vec.push_back(t5);
  for (auto iter = vec.begin(); iter != vec.end(); iter++)
  {
    vec.erase(remove_if(vec.begin(), vec.end(), Is_2), vec.end());
    std::cout << iter->a;
  }
  while (1);
  return 0;
}