Write a program that prompts the user to input a string.

the program then uses the function substr to remove all the vowels from the string.

for example, if str = "there", then after removing all the vowels, str = "thr".

after removing all the vowels, output the string.

your program must contain a function to remove all the vowels and a function to determine whether a character is a vowel.

#include <iostream>

using namespace std;

bool is_vowel(char c)

{

   switch(c)  //switch case to check if vowel is present

   {

       case 'a':

       case 'A':

       case 'e':

       case 'E':

       case 'i':

       case 'I':

       case 'o':

       case 'O':

       case 'u':

       case 'U': return true;

                 break;

       default : return false;

   }

}

string remove_vowel(string input)

{

   string str="";

   for(int i=0;input[i]!='\0';i++)

   {

       if(!is_vowel(input[i]))  //if vowel then not copied to substring

           str+=input[i];

   }

   return str;

}

int main()

{

   string str;

   cout<<"Enter string\n";

   cin>>str;

   cout<<"\nAfter removal of vowels substring is : "<<remove_vowel(str);  //substring is returned

   return 0;

}

OUTPUT :

Enter String

There

After removal of vowels substring is : Thr

Explanation:

The above program contains two methods in which one is is_vowel() which checks if the passed character is a vowel or not and the other method is remove_vowel() which removes all vowels from the string and returns a string which does not contain any vowel. This method passes every character of the string to the is_vowel() method and if false then it copies the character to the new string. At last, it returns a new string.  

the difference is right there dont you see it