GEMEENSCHAPPELIJKE DELERS VAN TWEE GETALLEN

Gegeven twee gehele getallen is het de taak om het aantal van alle gemene delers van gegeven getallen te vinden?

Voorbeelden:

Input : a = 12 b = 24 Output: 6 // all common divisors are 1 2 3 // 4 6 and 12 Input : a = 3 b = 17 Output: 1 // all common divisors are 1 Input : a = 20 b = 36 Output: 3 // all common divisors are 1 2 4

Recommended Practice Gemeenschappelijke delers Probeer het!

Het wordt aanbevolen om te verwijzen alle delers van een bepaald getal als voorwaarde voor dit artikel.

Naïeve oplossing
Een eenvoudige oplossing is om eerst alle delers van het eerste getal te vinden en deze in een array of hash op te slaan. Zoek vervolgens de gemene delers van het tweede getal en sla deze op. Druk ten slotte gemeenschappelijke elementen van twee opgeslagen arrays of hash af. De sleutel is dat de grootte van de machten van priemfactoren van een deler gelijk moet zijn aan de minimale macht van twee priemfactoren van a en b.

Vind de belangrijkste factoren van een gebruik priemfactorisatie .
Vind het aantal van elke priemfactor van A en bewaar deze in een Hashmap.
Prime factoriseren B met behulp van verschillende priemfactoren van A .
Dan zou het totale aantal delers gelijk zijn aan het product van (tel + 1)
van elke factor.

Dit geeft het aantal van alle delers van A En B .

C++

// C++ implementation of program  #include    using namespace std; // Map to store the count of each // prime factor of a  map<int int> ma; // Function that calculate the count of  // each prime factor of a number  void primeFactorize(int a)  {   for(int i = 2; i * i <= a; i += 2)   {   int cnt = 0;   while (a % i == 0)   {   cnt++;   a /= i;   }   ma[i] = cnt;   }   if (a > 1)  {  ma[a] = 1;  } }  // Function to calculate all common // divisors of two given numbers  // a b --> input integer numbers  int commDiv(int a int b)  {     // Find count of each prime factor of a   primeFactorize(a);   // stores number of common divisors   int res = 1;   // Find the count of prime factors   // of b using distinct prime factors of a   for(auto m = ma.begin();  m != ma.end(); m++)  {  int cnt = 0;   int key = m->first;   int value = m->second;   while (b % key == 0)   {   b /= key;   cnt++;   }   // Prime factor of common divisor   // has minimum cnt of both a and b   res *= (min(cnt value) + 1);   }   return res;  }  // Driver code  int main() {  int a = 12 b = 24;     cout << commDiv(a b) << endl;     return 0; } // This code is contributed by divyeshrabadiya07

Java

// Java implementation of program import java.util.*; import java.io.*; class GFG {  // map to store the count of each prime factor of a  static HashMap<Integer Integer> ma = new HashMap<>();  // method that calculate the count of  // each prime factor of a number  static void primeFactorize(int a)  {  for (int i = 2; i * i <= a; i += 2) {  int cnt = 0;  while (a % i == 0) {  cnt++;  a /= i;  }  ma.put(i cnt);  }  if (a > 1)  ma.put(a 1);  }  // method to calculate all common divisors  // of two given numbers  // a b --> input integer numbers  static int commDiv(int a int b)  {  // Find count of each prime factor of a  primeFactorize(a);  // stores number of common divisors  int res = 1;  // Find the count of prime factors of b using  // distinct prime factors of a  for (Map.Entry<Integer Integer> m : ma.entrySet()) {  int cnt = 0;  int key = m.getKey();  int value = m.getValue();  while (b % key == 0) {  b /= key;  cnt++;  }  // prime factor of common divisor  // has minimum cnt of both a and b  res *= (Math.min(cnt value) + 1);  }  return res;  }  // Driver method  public static void main(String args[])  {  int a = 12 b = 24;  System.out.println(commDiv(a b));  } }

Python3

# Python3 implementation of program  import math # Map to store the count of each # prime factor of a  ma = {} # Function that calculate the count of  # each prime factor of a number  def primeFactorize(a): sqt = int(math.sqrt(a)) for i in range(2 sqt 2): cnt = 0 while (a % i == 0): cnt += 1 a /= i ma[i] = cnt if (a > 1): ma[a] = 1 # Function to calculate all common # divisors of two given numbers  # a b --> input integer numbers  def commDiv(a b): # Find count of each prime factor of a  primeFactorize(a) # stores number of common divisors  res = 1 # Find the count of prime factors  # of b using distinct prime factors of a  for key value in ma.items(): cnt = 0 while (b % key == 0): b /= key cnt += 1 # Prime factor of common divisor  # has minimum cnt of both a and b  res *= (min(cnt value) + 1) return res # Driver code  a = 12 b = 24 print(commDiv(a b)) # This code is contributed by Stream_Cipher

// C# implementation of program using System; using System.Collections.Generic;  class GFG{   // Map to store the count of each  // prime factor of a static Dictionary<int  int> ma = new Dictionary<int  int>(); // Function that calculate the count of // each prime factor of a number static void primeFactorize(int a) {  for(int i = 2; i * i <= a; i += 2)  {  int cnt = 0;  while (a % i == 0)  {  cnt++;  a /= i;  }  ma.Add(i cnt);  }    if (a > 1)  ma.Add(a 1); } // Function to calculate all common  // divisors of two given numbers // a b --> input integer numbers static int commDiv(int a int b) {    // Find count of each prime factor of a  primeFactorize(a);    // Stores number of common divisors  int res = 1;    // Find the count of prime factors  // of b using distinct prime factors of a  foreach(KeyValuePair<int int> m in ma)  {  int cnt = 0;  int key = m.Key;  int value = m.Value;    while (b % key == 0)  {  b /= key;  cnt++;  }  // Prime factor of common divisor  // has minimum cnt of both a and b  res *= (Math.Min(cnt value) + 1);  }  return res; } // Driver code  static void Main() {  int a = 12 b = 24;    Console.WriteLine(commDiv(a b)); } } // This code is contributed by divyesh072019

JavaScript

<script>   // JavaScript implementation of program  // Map to store the count of each  // prime factor of a  let ma = new Map();  // Function that calculate the count of  // each prime factor of a number  function primeFactorize(a)  {  for(let i = 2; i * i <= a; i += 2)  {  let cnt = 0;  while (a % i == 0)  {  cnt++;  a = parseInt(a / i 10);  }  ma.set(i cnt);  }  if (a > 1)  {  ma.set(a 1);  }  }  // Function to calculate all common  // divisors of two given numbers  // a b --> input integer numbers  function commDiv(ab)  {  // Find count of each prime factor of a  primeFactorize(a);  // stores number of common divisors  let res = 1;  // Find the count of prime factors  // of b using distinct prime factors of a  ma.forEach((valueskeys)=>{  let cnt = 0;  let key = keys;  let value = values;  while (b % key == 0)  {  b = parseInt(b / key 10);  cnt++;  }  // Prime factor of common divisor  // has minimum cnt of both a and b  res *= (Math.min(cnt value) + 1);  })  return res;  }  // Driver code  let a = 12 b = 24;    document.write(commDiv(a b));   </script>

Uitgang:

Tijdcomplexiteit : O(?n log n)
Hulpruimte: Op)

Efficiënte oplossing -
Een betere oplossing is om de grootste gemene deler (ggd) van gegeven twee getallen en tel vervolgens de delers van die ggd.

C++

// C++ implementation of program #include    using namespace std; // Function to calculate gcd of two numbers int gcd(int a int b) {  if (a == 0)  return b;  return gcd(b % a a); } // Function to calculate all common divisors // of two given numbers // a b --> input integer numbers int commDiv(int a int b) {  // find gcd of a b  int n = gcd(a b);  // Count divisors of n.  int result = 0;  for (int i = 1; i <= sqrt(n); i++) {  // if 'i' is factor of n  if (n % i == 0) {  // check if divisors are equal  if (n / i == i)  result += 1;  else  result += 2;  }  }  return result; } // Driver program to run the case int main() {  int a = 12 b = 24;  cout << commDiv(a b);  return 0; }

Java

// Java implementation of program class Test {  // method to calculate gcd of two numbers  static int gcd(int a int b)  {  if (a == 0)  return b;  return gcd(b % a a);  }  // method to calculate all common divisors  // of two given numbers  // a b --> input integer numbers  static int commDiv(int a int b)  {  // find gcd of a b  int n = gcd(a b);  // Count divisors of n.  int result = 0;  for (int i = 1; i <= Math.sqrt(n); i++) {  // if 'i' is factor of n  if (n % i == 0) {  // check if divisors are equal  if (n / i == i)  result += 1;  else  result += 2;  }  }  return result;  }  // Driver method  public static void main(String args[])  {  int a = 12 b = 24;  System.out.println(commDiv(a b));  } }

Python3

# Python implementation of program from math import sqrt # Function to calculate gcd of two numbers def gcd(a b): if a == 0: return b return gcd(b % a a) # Function to calculate all common divisors  # of two given numbers  # a b --> input integer numbers  def commDiv(a b): # find GCD of a b n = gcd(a b) # Count divisors of n result = 0 for i in range(1int(sqrt(n))+1): # if i is a factor of n if n % i == 0: # check if divisors are equal if n/i == i: result += 1 else: result += 2 return result # Driver program to run the case  if __name__ == '__main__': a = 12 b = 24; print(commDiv(a b))

// C# implementation of program using System; class GFG {  // method to calculate gcd  // of two numbers  static int gcd(int a int b)  {  if (a == 0)  return b;  return gcd(b % a a);  }  // method to calculate all  // common divisors of two  // given numbers a b -->  // input integer numbers  static int commDiv(int a int b)  {  // find gcd of a b  int n = gcd(a b);  // Count divisors of n.  int result = 0;  for (int i = 1; i <= Math.Sqrt(n); i++) {  // if 'i' is factor of n  if (n % i == 0) {  // check if divisors are equal  if (n / i == i)  result += 1;  else  result += 2;  }  }  return result;  }  // Driver method  public static void Main(String[] args)  {  int a = 12 b = 24;  Console.Write(commDiv(a b));  } } // This code contributed by parashar.

PHP

 // PHP implementation of program // Function to calculate  // gcd of two numbers function gcd($a $b) { if ($a == 0) return $b; return gcd($b % $a $a); } // Function to calculate all common  // divisors of two given numbers // a b --> input integer numbers function commDiv($a $b) { // find gcd of a b $n = gcd($a $b); // Count divisors of n. $result = 0; for ($i = 1; $i <= sqrt($n); $i++) { // if 'i' is factor of n if ($n % $i == 0) { // check if divisors  // are equal if ($n / $i == $i) $result += 1; else $result += 2; } } return $result; } // Driver Code $a = 12; $b = 24; echo(commDiv($a $b)); // This code is contributed by Ajit. ?>

JavaScript

<script>  // Javascript implementation of program    // Function to calculate gcd of two numbers  function gcd(a b)  {  if (a == 0)  return b;  return gcd(b % a a);  }  // Function to calculate all common divisors  // of two given numbers  // a b --> input integer numbers  function commDiv(a b)  {  // find gcd of a b  let n = gcd(a b);  // Count divisors of n.  let result = 0;  for (let i = 1; i <= Math.sqrt(n); i++) {  // if 'i' is factor of n  if (n % i == 0) {  // check if divisors are equal  if (n / i == i)  result += 1;  else  result += 2;  }  }  return result;  }  let a = 12 b = 24;  document.write(commDiv(a b));   </script>

Uitgang:

Tijdcomplexiteit: Op^1/2) waarbij n de ggd is van twee getallen.
Hulpruimte: O(1)

Een andere aanpak:

1. Definieer een functie 'ggd' die twee gehele getallen 'a' en 'b' neemt en hun grootste gemene deler (GCD) retourneert met behulp van het Euclidische algoritme.
2. Definieer een functie 'count_common_divisors' die twee gehele getallen 'a' en 'b' neemt en het aantal gemeenschappelijke delers van 'a' en 'b' telt met behulp van hun GCD.
3. Bereken de GCD van 'a' en 'b' met behulp van de functie 'ggd'.
4. Initialiseer een teller 'telling' naar 0.
5. Loop door alle mogelijke delers van de GCD van 'a' en 'b' van 1 naar de vierkantswortel van de GCD.
6. Als de huidige deler de GCD deelt, verhoog dan de teller met 2 (omdat zowel 'a' als 'b' deelbaar zijn door de deler).
7. Als het kwadraat van de huidige deler gelijk is aan de GCD, verlaag dan de teller met 1 (omdat we deze deler al één keer hebben geteld).
8. Bereken het uiteindelijke aantal gemene delers.
9. Definieer in de hoofdfunctie twee gehele getallen 'a' en 'b' en roep de functie 'count_common_divisors' aan met deze gehele getallen.
10. Druk het aantal gemene delers van 'a' en 'b' af met behulp van de printf-functie.

#include  int gcd(int a int b) {  if(b == 0) {  return a;  }  return gcd(b a % b); } int count_common_divisors(int a int b) {  int gcd_ab = gcd(a b);  int count = 0;  for(int i = 1; i * i <= gcd_ab; i++) {  if(gcd_ab % i == 0) {  count += 2;  if(i * i == gcd_ab) {  count--;  }  }  }  return count; } int main() {  int a = 12;  int b = 18;  int common_divisors = count_common_divisors(a b);  printf('The number of common divisors of %d and %d is %d.n' a b common_divisors);  return 0; }

C++

#include    using namespace std; int gcd(int a int b) {  if(b == 0) {  return a;  }  return gcd(b a % b); } int count_common_divisors(int a int b) {  int gcd_ab = gcd(a b);  int count = 0;  for(int i = 1; i * i <= gcd_ab; i++) {  if(gcd_ab % i == 0) {  count += 2;  if(i * i == gcd_ab) {  count--;  }  }  }  return count; } int main() {  int a = 12;  int b = 18;  int common_divisors = count_common_divisors(a b);  cout<<'The number of common divisors of '<<a<<' and '<<b<<' is '<<common_divisors<<'.'<<endl;  return 0; }

Java

import java.util.*; public class Main {  public static int gcd(int a int b) {  if(b == 0) {  return a;  }  return gcd(b a % b);  }  public static int countCommonDivisors(int a int b) {  int gcd_ab = gcd(a b);  int count = 0;  for(int i = 1; i * i <= gcd_ab; i++) {  if(gcd_ab % i == 0) {  count += 2;  if(i * i == gcd_ab) {  count--;  }  }  }  return count;  }  public static void main(String[] args) {  int a = 12;  int b = 18;  int commonDivisors = countCommonDivisors(a b);  System.out.println('The number of common divisors of ' + a + ' and ' + b + ' is ' + commonDivisors + '.');  } }

Python3

import math def gcd(a b): if b == 0: return a return gcd(b a % b) def count_common_divisors(a b): gcd_ab = gcd(a b) count = 0 for i in range(1 int(math.sqrt(gcd_ab)) + 1): if gcd_ab % i == 0: count += 2 if i * i == gcd_ab: count -= 1 return count a = 12 b = 18 common_divisors = count_common_divisors(a b) print('The number of common divisors of' a 'and' b 'is' common_divisors '.') # This code is contributed by Prajwal Kandekar

using System; public class MainClass {  public static int GCD(int a int b)  {  if (b == 0)  {  return a;  }  return GCD(b a % b);  }  public static int CountCommonDivisors(int a int b)  {  int gcd_ab = GCD(a b);  int count = 0;  for (int i = 1; i * i <= gcd_ab; i++)  {  if (gcd_ab % i == 0)  {  count += 2;  if (i * i == gcd_ab)  {  count--;  }  }  }  return count;  }  public static void Main()  {  int a = 12;  int b = 18;  int commonDivisors = CountCommonDivisors(a b);  Console.WriteLine('The number of common divisors of {0} and {1} is {2}.' a b commonDivisors);  } }

JavaScript

// Function to calculate the greatest common divisor of  // two integers a and b using the Euclidean algorithm function gcd(a b) {  if(b === 0) {  return a;  }  return gcd(b a % b); } // Function to count the number of common divisors of two integers a and b function count_common_divisors(a b) {  let gcd_ab = gcd(a b);  let count = 0;  for(let i = 1; i * i <= gcd_ab; i++) {  if(gcd_ab % i === 0) {  count += 2;  if(i * i === gcd_ab) {  count--;  }  }  }  return count; } let a = 12; let b = 18; let common_divisors = count_common_divisors(a b); console.log(`The number of common divisors of ${a} and ${b} is ${common_divisors}.`);

Uitvoer

The number of common divisors of 12 and 18 is 4.

De tijdscomplexiteit van de functie ggd() is O(log(min(a b))) omdat deze het algoritme van Euclides gebruikt dat logaritmische tijd in beslag neemt ten opzichte van het kleinste van de twee getallen.

De tijdscomplexiteit van de functie count_common_divisors() is O(sqrt(gcd(a b))) terwijl deze itereert tot aan de vierkantswortel van de ggd van de twee getallen.

De ruimtecomplexiteit van beide functies is O(1), omdat ze slechts een constante hoeveelheid geheugen gebruiken, ongeacht de invoergrootte.

TechCodeview

Gemeenschappelijke delers van twee getallen

Een andere aanpak: