Dada una string str que contiene solo caracteres en minúsculas. La tarea es imprimir los caracteres que tienen frecuencia principal en el orden en que aparecen.
Tenga en cuenta que los elementos repetidos con frecuencias principales se imprimen tantas veces como aparecen en el orden en que aparecen.
Ejemplos:
Entrada: str = «geeksforgeeks»
Salida: gksgks
Personaje Frecuencia ‘gramo’ 2 ‘mi’ 4 ‘k’ 2 ‘s’ 2 ‘F’ 1 ‘o’ 1 ‘r’ 1 ‘g’, ‘k’ y ‘s’ son los únicos caracteres con frecuencias principales.
Entrada: str = “avión”
Salida: aeae
Enfoque: Cree una array de frecuencia para almacenar la frecuencia de cada uno de los caracteres de la string str dada . Recorra la string str nuevamente y verifique si la frecuencia de ese carácter es principal usando Sieve Of Eratosthenes .
A continuación se muestra la implementación del enfoque anterior:
C++
// C++ implementation of the approach
#include <bits/stdc++.h>
using namespace std;
#define SIZE 26
// Function to create Sieve to check primes
void SieveOfEratosthenes(bool prime[], int p_size)
{
// false here indicates
// that it is not prime
prime[0] = false;
prime[1] = false;
for (int p = 2; p * p <= p_size; p++) {
// If prime[p] is not changed,
// then it is a prime
if (prime[p]) {
// Update all multiples of p,
// set them to non-prime
for (int i = p * 2; i <= p_size; i += p)
prime[i] = false;
}
}
}
// Function to print the prime frequency characters
// in the order of their occurrence
void printChar(string str, int n)
{
bool prime[n + 1];
memset(prime, true, sizeof(prime));
// Function to create Sieve to check primes
SieveOfEratosthenes(prime, str.length() + 1);
// To store the frequency of each of
// the character of the string
int freq[SIZE];
// Initialize all elements of freq[] to 0
memset(freq, 0, sizeof(freq));
// Update the frequency of each character
for (int i = 0; i < n; i++)
freq[str[i] - 'a']++;
// Traverse str character by character
for (int i = 0; i < n; i++) {
// If frequency of current character is prime
if (prime[freq[str[i] - 'a']]) {
cout << str[i];
}
}
}
// Driver code
int main()
{
string str = "geeksforgeeks";
int n = str.length();
printChar(str, n);
return 0;
}
Java
// Java implementation of the approach
class GFG
{
static int SIZE = 26;
// Function to create Sieve to check primes
static void SieveOfEratosthenes(boolean []prime,
int p_size)
{
// false here indicates
// that it is not prime
prime[0] = false;
prime[1] = false;
for (int p = 2; p * p <= p_size; p++)
{
// If prime[p] is not changed,
// then it is a prime
if (prime[p])
{
// Update all multiples of p,
// set them to non-prime
for (int i = p * 2; i < p_size; i += p)
prime[i] = false;
}
}
}
// Function to print the prime frequency characters
// in the order of their occurrence
static void printChar(String str, int n)
{
boolean []prime = new boolean[n + 1];
for(int i = 0; i < n + 1; i++)
prime[i] = true;
// Function to create Sieve to check primes
SieveOfEratosthenes(prime, str.length() + 1);
// To store the frequency of each of
// the character of the string
int []freq = new int[SIZE];
// Initialize all elements of freq[] to 0
for(int i =0; i< SIZE; i++)
freq[i]=0;
// Update the frequency of each character
for (int i = 0; i < n; i++)
freq[str.charAt(i) - 'a']++;
// Traverse str character by character
for (int i = 0; i < n; i++)
{
// If frequency of current character is prime
if (prime[freq[str.charAt(i) - 'a']])
{
System.out.print(str.charAt(i));
}
}
}
// Driver code
public static void main(String[] args)
{
String str = "geeksforgeeks";
int n = str.length();
printChar(str, n);
}
}
// This code is contributed by PrinciRaj1992
Python3
# Python 3 implementation of the approach
SIZE = 26
from math import sqrt
# Function to create Sieve to check primes
def SieveOfEratosthenes(prime, p_size):
# false here indicates
# that it is not prime
prime[0] = False
prime[1] = False
for p in range(2, int(sqrt(p_size)), 1):
# If prime[p] is not changed,
# then it is a prime
if (prime[p]):
# Update all multiples of p,
# set them to non-prime
for i in range(p * 2, p_size, p):
prime[i] = False
# Function to print the prime frequency characters
# in the order of their occurrence
def printChar(str, n):
prime = [True for i in range(n + 1)]
# Function to create Sieve to check primes
SieveOfEratosthenes(prime, len(str) + 1)
# To store the frequency of each of
# the character of the string
freq = [0 for i in range(SIZE)]
# Update the frequency of each character
for i in range(n):
freq[ord(str[i]) - ord('a')] += 1
# Traverse str character by character
for i in range(n):
# If frequency of current character is prime
if (prime[freq[ord(str[i]) - ord('a')]]):
print(str[i], end = "")
# Driver code
if __name__ == '__main__':
str = "geeksforgeeks"
n = len(str)
printChar(str, n)
# This code is contributed by Surendra_Gangwar
C#
// C# implementation of the approach
using System;
class GFG
{
static int SIZE = 26;
// Function to create Sieve to check primes
static void SieveOfEratosthenes(bool[] prime,
int p_size)
{
// false here indicates
// that it is not prime
prime[0] = false;
prime[1] = false;
for (int p = 2; p * p <= p_size; p++)
{
// If prime[p] is not changed,
// then it is a prime
if (prime[p])
{
// Update all multiples of p,
// set them to non-prime
for (int i = p * 2;
i < p_size; i += p)
prime[i] = false;
}
}
}
// Function to print the prime frequency characters
// in the order of their occurrence
static void printChar(string str, int n)
{
bool[] prime = new bool[n + 1];
for (int i = 0; i < n + 1; i++)
prime[i] = true;
// Function to create Sieve to check primes
SieveOfEratosthenes(prime, str.Length + 1);
// To store the frequency of each of
// the character of the string
int[] freq = new int[SIZE];
// Initialize all elements of freq[] to 0
for (int i = 0; i < SIZE; i++)
freq[i] = 0;
// Update the frequency of each character
for (int i = 0; i < n; i++)
freq[str[i] - 'a']++;
// Traverse str character by character
for (int i = 0; i < n; i++)
{
// If frequency of current character is prime
if (prime[freq[str[i] - 'a']])
{
Console.Write(str[i]);
}
}
}
// Driver code
public static void Main(String[] args)
{
String str = "geeksforgeeks";
int n = str.Length;
printChar(str, n);
}
}
// This code is contributed by
// sanjeev2552
Javascript
<script>
// javaScript implementation of the approach
let SIZE = 26;
// Function to create Sieve to check primes
// Function to create Sieve to check primes
function SieveOfEratosthenes(prime, p_size){
// False here indicates
// that it is not prime
prime[0] = false;
prime[1] = false;
for (let p = 2; p * p <= p_size; p++) {
// If prime[p] is not changed,
// then it is a prime
if (prime[p]) {
// Update all multiples of p,
// set them to non-prime
for (let i = p * 2; i <= p_size; i += p)
prime[i] = false;
}
}
return prime;
}
// Function to print the prime frequency characters
// in the order of their occurrence
function printChar(str, n){
let prime = [];
for(let i = 0; i<n+1; i++){
prime.push(true);
}
// Function to create Sieve to check primes
prime = SieveOfEratosthenes(prime, str.length + 1);
// To store the frequency of each of
// the character of the string
let freq = [];
for(let i = 0; i<26; i++){
freq.push(0);
}
// Update the frequency of each character
for (let i = 0; i < n; i++)
freq[str.charCodeAt(i) - 97]++;
// Traverse str character by character
for (let i = 0; i < n; i++) {
// If frequency of current character is prime
if (prime[freq[str.charCodeAt(i) - 97]]) {
document.write(str[i]);
}
}
}
// Driver code
let str = "geeksforgeeks";
let n = str.length;
printChar(str, n);
</script>
Producción
gksgks
Complejidad de tiempo: O(n)
Espacio Auxiliar: O(n)
Método #2: Uso de funciones integradas:
Acercarse:
Escanearemos la string y contaremos la ocurrencia de todos los caracteres usando la función Counter() incorporada, luego recorremos la string y verificamos si las ocurrencias son principales o no, si hay alguna frecuencia principal y luego la imprimimos.
Nota: Este método es aplicable para todo tipo de caracteres
A continuación se muestra la implementación del enfoque anterior:
C++
// C++ code for the above approach
#include <bits/stdc++.h>
using namespace std;
// Function to check primes
bool prime(int n)
{
if (n <= 1)
return false;
int max_div = floor(sqrt(n));
for (int i = 2; i < 1 + max_div; i++) {
if (n % i == 0)
return false;
}
return true;
}
void checkString(string s)
{
// Counting the frequency of all
// character using Counter function
unordered_map<char, int> freq;
for (int i = 0; i < s.size(); i++) {
freq[s[i]]++;
}
// Traversing string
for (int i = 0; i < s.size(); i++) {
if (prime(freq[s[i]]))
cout << s[i];
}
}
// Driver code
int main()
{
string s = "geeksforgeeks";
// Passing string to checkString function
checkString(s);
}
// This code is contributed by Samim Hossain Mondal.
Java
// Java code for the above approach
import java.io.*;
import java.util.*;
class GFG {
// Function to check primes
static boolean prime(int n)
{
if (n <= 1)
return false;
int max_div = (int)Math.floor(Math.sqrt(n));
for(int i = 2; i < 1 + max_div; i++)
{
if (n % i == 0)
return false;
}
return true;
}
static void checkString(String s)
{
// Counting the frequency of all
// character using Counter function
Map<Character, Integer> freq = new HashMap<Character, Integer>();
for(int i = 0; i < s.length(); i++)
{
if (!freq.containsKey(s.charAt(i)))
freq.put(s.charAt(i),0);
freq.put(s.charAt(i),freq.get(s.charAt(i))+1);
}
// Traversing string
for(int i = 0; i < s.length(); i++)
{
if (prime(freq.get(s.charAt(i))))
System.out.print(s.charAt(i));
}
}
// Driver code
public static void main (String[] args) {
String s = "geeksforgeeks";
// Passing string to checkString function
checkString(s);
}
}
// This code is contributed by avanitrachhadiya2155
Python3
# Python code for the above approach # importing Counter function from collections import Counter import math # Function to check primes def prime(n): if n <= 1: return False max_div = math.floor(math.sqrt(n)) for i in range(2, 1 + max_div): if n % i == 0: return False return True def checkString(s): # Counting the frequency of all # character using Counter function freq = Counter(s) # Traversing string for i in range(len(s)): if prime(freq[s[i]]): print(s[i], end="") # Driver code s = "geeksforgeeks" # passing string to checkString function checkString(s) # This code is contributed by vikkycirus
C#
// C# code for the above approach
using System;
using System.Collections.Generic;
class GFG{
// Function to check primes
static bool prime(int n)
{
if (n <= 1)
return false;
int max_div = (int)Math.Floor(Math.Sqrt(n));
for(int i = 2; i < 1 + max_div; i++)
{
if (n % i == 0)
return false;
}
return true;
}
static void checkString(string s)
{
// Counting the frequency of all
// character using Counter function
Dictionary<char,
int> freq = new Dictionary<char,
int>();
for(int i = 0; i < s.Length; i++)
{
if (!freq.ContainsKey(s[i]))
freq[s[i]] = 0;
freq[s[i]] += 1;
}
// Traversing string
for(int i = 0; i < s.Length; i++)
{
if (prime(freq[s[i]]))
Console.Write(s[i]);
}
}
// Driver code
public static void Main()
{
string s = "geeksforgeeks";
// Passing string to checkString function
checkString(s);
}
}
// This code is contributed by ukasp
Javascript
<script>
// Javascript code for the above approach
// Function to check primes
function prime(n)
{
if (n <= 1)
return false;
let max_div = Math.floor(Math.sqrt(n));
for(let i = 2; i < 1 + max_div; i++)
{
if (n % i == 0)
return false;
}
return true;
}
function checkString(s)
{
// Counting the frequency of all
// character using Counter function
let freq = new Map();
for(let i = 0; i < s.length; i++)
{
if (!freq.has(s[i]))
freq.set(s[i], 0);
freq.set(s[i], freq.get(s[i]) + 1);
}
// Traversing string
for(let i = 0; i < s.length; i++)
{
if (prime(freq.get(s[i])))
document.write(s[i]);
}
}
// Driver code
let s = "geeksforgeeks";
// Passing string to checkString function
checkString(s);
// This code is contributed by rag2127
</script>
Producción
gksgks
Complejidad de tiempo: O(n)
Espacio Auxiliar: O(26)
Publicación traducida automáticamente
Artículo escrito por NikhilRathor y traducido por Barcelona Geeks. The original can be accessed here. Licence: CCBY-SA