def sieve_(self, still_alive_idxes):
    self.N = self.N[still_alive_idxes]
    self.pool = self.pool[still_alive_idxes]
    self.utilities = self.utilities[still_alive_idxes]
    self.last_proposal = self.last_proposal[still_alive_idxes]
    self.m_prev = self.m_prev[still_alive_idxes]
def sieve_(self, still_alive_idxes):
    self.N = self.N[still_alive_idxes]
    self.pool = self.pool[still_alive_idxes]
    self.utilities = self.utilities[still_alive_idxes]
    self.last_proposal = self.last_proposal[still_alive_idxes]
    self.m_prev = self.m_prev[still_alive_idxes]