#include <iostream> #include <algorithm> #include <vector> #include <cmath> using namespace std; typedef long long ll; typedef pair<int, int> pii; typedef vector<int> vi; int main() { ios::sync_with_stdio(false); cin.tie(0); int n, res = 0; cin >> n; vector<int> divisors = {1}; for (int i = 2; i * i < n; ++i) { if (n % i == 0) { if (7 * i <= n) divisors.push_back(i); if (n / i <= n / 7) divisors.push_back(n/i); } } int sqr = static_cast<int>(sqrt(n)); if (sqr * sqr == n) divisors.push_back(sqr); //cout << "Divs: " << divisors.size() << endl; for (int a : divisors) { /*for (int k = 2; n - a > 2 * k * a; ++k) { if ( (n/a - 1) % k != 0 ) continue; if ( (n - a - k * a) % (k * a) == 0) { ++res; //cout << a << " " << k * a << " " << n - a - k*a << '\n'; } }*/ int dividend = n/a - 1; for (int i = 2; i * i < dividend; ++i) { if (dividend % i == 0) { int k1 = i, k2 = dividend/i; if ( n - a > 2*k1*a && (n - a - k1 * a) % (k1 * a) == 0) { ++res; //cout << a << " " << k1 * a << " " << n - a - k1*a << '\n'; } if ( n - a > 2*k2*a && (n - a - k2 * a) % (k2 * a) == 0) { ++res; //cout << a << " " << k2 * a << " " << n - a - k2*a << '\n'; } } } int sq = static_cast<int>(sqrt(dividend)); if (sq * sq == dividend) if ( n - a > 2*sq*a && (n - a - sq * a) % (sq * a) == 0) { ++res; //cout << a << " " << sq * a << " " << n - a - sq*a << '\n'; } } cout << res << '\n'; return 0; }
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 | #include <iostream> #include <algorithm> #include <vector> #include <cmath> using namespace std; typedef long long ll; typedef pair<int, int> pii; typedef vector<int> vi; int main() { ios::sync_with_stdio(false); cin.tie(0); int n, res = 0; cin >> n; vector<int> divisors = {1}; for (int i = 2; i * i < n; ++i) { if (n % i == 0) { if (7 * i <= n) divisors.push_back(i); if (n / i <= n / 7) divisors.push_back(n/i); } } int sqr = static_cast<int>(sqrt(n)); if (sqr * sqr == n) divisors.push_back(sqr); //cout << "Divs: " << divisors.size() << endl; for (int a : divisors) { /*for (int k = 2; n - a > 2 * k * a; ++k) { if ( (n/a - 1) % k != 0 ) continue; if ( (n - a - k * a) % (k * a) == 0) { ++res; //cout << a << " " << k * a << " " << n - a - k*a << '\n'; } }*/ int dividend = n/a - 1; for (int i = 2; i * i < dividend; ++i) { if (dividend % i == 0) { int k1 = i, k2 = dividend/i; if ( n - a > 2*k1*a && (n - a - k1 * a) % (k1 * a) == 0) { ++res; //cout << a << " " << k1 * a << " " << n - a - k1*a << '\n'; } if ( n - a > 2*k2*a && (n - a - k2 * a) % (k2 * a) == 0) { ++res; //cout << a << " " << k2 * a << " " << n - a - k2*a << '\n'; } } } int sq = static_cast<int>(sqrt(dividend)); if (sq * sq == dividend) if ( n - a > 2*sq*a && (n - a - sq * a) % (sq * a) == 0) { ++res; //cout << a << " " << sq * a << " " << n - a - sq*a << '\n'; } } cout << res << '\n'; return 0; } |