Problem p00646 (C++)

Buggy submission (status: Time Limit Exceeded):
#include <algorithm>
#include <iostream>
#include <map>
#include <vector>
using namespace std;

const long long int MAX_ = 10000000;
vector<long long int> prime;
bool is_prime[MAX_];

void sieve() {
  fill(is_prime, is_prime + MAX_, true);
  is_prime[0] = is_prime[1] = false;
  for (long long int i = 2; i < MAX_; ++i) {
    if (is_prime[i]) {
      prime.push_back(i);
      for (long long int j = i * 2; j < MAX_; j += i) {
        is_prime[j] = false;
      }
    }
  }
}

long long int gcd(long long int a, long long int b) {
  while (b != 0) {
    long long int tmp = a % b;
    a = b;
    b = tmp;
  }
  return a;
}

vector<long long int> *divisor(long long int x) {
  static vector<long long int> result;
  result.clear();
  for (long long int i = 1; i * i <= x; ++i) {
    if (x % i == 0) {
      result.push_back(i);
      long long int tmp = x / i;
      if (i != tmp)
        result.push_back(tmp);
    }
  }
  sort(result.begin(), result.end());
  return &result;
}

map<long long int, long long int> *prime_factor(long long int n) {
  static map<long long int, long long int> result;
  result.clear();
  for (auto it = prime.begin(); (*it) * (*it) <= n && it != prime.end(); ++it) {
    while (n % (*it) == 0) {
      ++result[(*it)];
      n /= (*it);
    }
  }
  if (n != 1)
    result[n] = 1;
  return &result;
}

int solve(long long int l) {
  int ans = 0;
  vector<long long int> v = (*divisor(l));
  map<long long int, long long int> table = (*prime_factor(l));
  for (auto it = v.begin(); it != v.end(); ++it) {
    /*
    for(auto it_=v.begin(); (*it_)<=(*it)&&it_!=v.end(); ++it_){
            if((*it)*(*it_)/gcd((*it),(*it_))==l) ++ans;
    }
    */
    map<long long int, long long int> table_ = (*prime_factor(*it));
    long long int tmp = 1;
    for (auto it_ = table.begin(); it_ != table.end(); ++it_) {
      if (table_[it_->first] == it_->second)
        tmp *= it_->second + 1;
      // cout << it_->second << endl;
    }
    // cout << tmp << endl;
    ans += tmp;
  }
  ans = (ans + 1) / 2;
  return ans;
}

int main() {
  sieve();
  long long int L;
  while (cin >> L && L) {
    cout << solve(L) << endl;
  }
  return 0;
}

Fixed submission:
#include <algorithm>
#include <iostream>
#include <map>
#include <vector>
using namespace std;

const long long int MAX_ = 1000000;
vector<long long int> prime;
bool is_prime[MAX_];

void sieve() {
  fill(is_prime, is_prime + MAX_, true);
  is_prime[0] = is_prime[1] = false;
  for (long long int i = 2; i < MAX_; ++i) {
    if (is_prime[i]) {
      prime.push_back(i);
      for (long long int j = i * 2; j < MAX_; j += i) {
        is_prime[j] = false;
      }
    }
  }
}

long long int gcd(long long int a, long long int b) {
  while (b != 0) {
    long long int tmp = a % b;
    a = b;
    b = tmp;
  }
  return a;
}

vector<long long int> *divisor(long long int x) {
  static vector<long long int> result;
  result.clear();
  for (long long int i = 1; i * i <= x; ++i) {
    if (x % i == 0) {
      result.push_back(i);
      long long int tmp = x / i;
      if (i != tmp)
        result.push_back(tmp);
    }
  }
  sort(result.begin(), result.end());
  return &result;
}

map<long long int, long long int> *prime_factor(long long int n) {
  static map<long long int, long long int> result;
  result.clear();
  for (auto it = prime.begin(); (*it) * (*it) <= n && it != prime.end(); ++it) {
    while (n % (*it) == 0) {
      ++result[(*it)];
      n /= (*it);
    }
  }
  if (n != 1)
    result[n] = 1;
  return &result;
}

int solve(long long int l) {
  int ans = 0;
  vector<long long int> v = (*divisor(l));
  map<long long int, long long int> table = (*prime_factor(l));
  for (auto it = v.begin(); it != v.end(); ++it) {
    /*
    for(auto it_=v.begin(); (*it_)<=(*it)&&it_!=v.end(); ++it_){
            if((*it)*(*it_)/gcd((*it),(*it_))==l) ++ans;
    }
    */
    map<long long int, long long int> table_ = (*prime_factor(*it));
    long long int tmp = 1;
    for (auto it_ = table.begin(); it_ != table.end(); ++it_) {
      if (table_[it_->first] == it_->second)
        tmp *= it_->second + 1;
      // cout << it_->second << endl;
    }
    // cout << tmp << endl;
    ans += tmp;
  }
  ans = (ans + 1) / 2;
  return ans;
}

int main() {
  sieve();
  long long int L;
  while (cin >> L && L) {
    cout << solve(L) << endl;
  }
  return 0;
}