#include <iostream>
#include <fstream>
#include <cstdlib>


std::string word; 
std::string longest_word; 
using namespace std;

bool is_single_vowel(string word){
     //all words contain at least 1 vowel; find it:
           size_t found = word.find_first_of("aeiouAEIOU");
           //Handle Speacial Case: If no vowel was detected, 
           // word must be using single 'y' as a vowel:
           
           if(found == string::npos)
           return true;
           
       //Attempt to find any occurance of a second vowel
       found = word.find_first_of("aeiouAEIOU", found +1);
       
       //If no second vowel was detected, return TRUE
       if(found == string::npos)
       return true;
       //Else word contains two or more vowels
       else
       return false;
}



int main()
{
 ifstream inStream;
 
 string  word;
 string longest_word;
int size;

inStream.open("words.txt", ifstream ::in);




//for (int i = 0; i< 50000; i++)

while(inStream) {
       
       inStream >> word;
       

      cout << word[ 0 ];
      system("pause");

    if (word.size () > longest_word.size () && is_single_vowel(word))
    longest_word = word;
    
    
   

} 


cout << "The longest word with one vowel is: " << longest_word << endl;
 
 inStream.close( );   
 
    system("PAUSE");
    return EXIT_SUCCESS;
}

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

  • Supports different platforms like Windows, various Linux flavours, MacOS etc
  • C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
  • Case-sensitive
  • C++ is a compiler based language
  • C++ supports structured programming language
  • C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
  • Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}