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Given a string
, the task is to remove all the consonants from the string and then print the string.Examples:
Input: str= “Welcome to geeksforgeeks”
Output: eoe o eeoee
Input: str= “What is your name?”
Output: a i ou ae?
Approach: Traverse all the characters of the
string, if the character is a consonant then remove it from the final answer.
Below is the implementation of the above approach:
Java
import java.util.Arrays;
import java.util.List;
class Test {
static boolean isAlphabet(char ch)
{
if (ch >= 'a' && ch <= 'z')
return true;
if (ch >= 'A'
&& ch <= 'Z')
return true;
return false;
}
static String remConsonants(String str)
{
Character vowels[]
= { 'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U' };
List<Character> al = Arrays.asList(vowels);
StringBuffer sb = new StringBuffer(str);
for
(int i = 0; i < sb.length(); i++) {
if (isAlphabet(sb.charAt(i))
&& !al.contains(sb.charAt(i))) {
sb.replace(i, i + 1, "");
i--;
}
}
return sb.toString();
}
public static void main(String[] args)
{
String str
= "GeeeksforGeeks - A Computer Science Portal for Geeks";
System.out.println(remConsonants(str));
}
}
Python3
def isAlphabet(ch):
if (ch >= 'a' and ch <= 'z'):
return True;
if (ch >= 'A' and ch <= 'Z'):
return True;
return False;
def remConsonants(str):
vowels =
[ 'a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U' ]
sb = "";
for i in range(len(str)):
present = False;
for j in range(len(vowels)):
if (str[i] == vowels[j]):
present = True;
break;
if (not isAlphabet(str[i]) or present ):
sb += str[i];
return sb;
if __name__=='__main__':
str = "GeeeksforGeeks - A Computer Science Portal for Geeks";
print(remConsonants(str));
C#
using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
class GFG{
static bool isAlphabet(char ch)
{
if (ch >= 'a' && ch <= 'z')
return true;
if (ch >= 'A' && ch <= 'Z')
return true;
return false;
}
static string
remConsonants(string str)
{
char []vowels = { 'a', 'e', 'i', 'o', 'u',
'A', 'E', 'I', 'O', 'U' };
string sb = "";
for(int i = 0; i < str.Length; i++)
{
bool present = false;
for(int j = 0; j < vowels.Length; j++)
{
if (str[i] == vowels[j])
{
present = true;
break;
}
}
if (!isAlphabet(str[i]) || present )
{
sb += str[i];
}
}
return sb;
}
public static void Main(string[] args)
{
string str = "GeeeksforGeeks - A Computer Science Portal for Geeks";
Console.Write(remConsonants(str));
}
}
Javascript
<script>
function isAlphabet(ch) {
if (ch >= "a" && ch <= "z") return true;
if (ch >= "A" && ch <= "Z") return true;
return false;
}
function remConsonants(str) {
var vowels =
["a", "e", "i", "o", "u", "A", "E", "I", "O", "U"];
var sb = "";
for (var i = 0; i < str.length; i++) {
var present = false;
for (var j = 0; j < vowels.length; j++) {
if (str[i] === vowels[j]) {
present = true;
break;
}
}
if (!isAlphabet(str[i]) || present) {
sb += str[i];
}
}
return sb;
}
var str =
"GeeeksforGeeks - A Computer Science Portal for Geeks";
document.write(remConsonants(str));
</script>
Output:
eeeoee - A oue iee oa o ee
Time Complexity: O(N)
Auxiliary Space: O(N)
Below is another program using Regular Expressions in Java
Java
class Test
{
static String remVowel(String str)
{
return str.replaceAll("[BCDFGHJKLMNPQRSTVXZbcdfghjklmnpqrstvxz]", "");
}
public static void main(String[] args)
{
String str = "GeeeksforGeeks - A Computer Science Portal for Geeks";
System.out.println(remVowel(str));
}
}
C#
using System;
using System.Text.RegularExpressions;
class GFG
{
static String remVowel(String str)
{
return Regex.Replace(str, "[BCDFGHJKLMNPQRSTVXZbcdfghjklmnpqrstvxz]", "");
}
public static void Main()
{
String str = "GeeeksforGeeks - A Computer Science Portal for Geeks";
Console.WriteLine(remVowel(str));
}
}
Output:
eeeoee - A oue iee oa o ee
Time complexity : O(n) where n is the length of string
Auxiliary Space: O(1)
How to remove consonants from a string using regular expressions in Java? Similarly, the following expression matches all the consonants in the given input string. "([^aeiouyAEIOUY0-9\W]+)"; Then you can remove the matched characters by replacing them with the empty string “”, using the replaceAll() method.
