unable to find out what is wrong

[reach devi]

I was trying to solve a problem in codeabbey.com. In this problem i have to output number of vowels per line of text.but i am not getting where my code has gone wrong.The output is always wrong.
Please can anyone explain me where i went wrong?
Its a bit urgent.
Note : the problem states that i should also take 'y' as a vowel.here is the code.

#include<iostream>
#include<string>
#include<cctype>

using namespace std;

bool isvowel(char c){
  if(c=='a'||c=='e'||c=='i'||c=='o'||c=='u'||c=='y')
    return true;
  else
    return false;
}

int main(){
  string str;
  int N,counter=0;
  cin >> N;
  while(N--){
    getline(cin,str);
	for(int i=0;i<str.size();i++)
	  if(isvowel(str.at(i))==true)
	    counter++;
	cout << counter << "  ";
	counter=0;
  }
  return 0;
}

[keskiverto]

Why the line 8, when line 9 uses c?

[reach devi]

@keskiverto You are right.thats a mistake.
But even after changing it, i am getting the wrong answer.

[MiiNiPaa]

You have problems with capital vowels. Apply tolower to the character tested in your isvowel function.

[reach devi]

@MiiNiPaa The problem says that there would be no capital vowels in the line.

[keskiverto]

Line 17 is formatted input. It leaves newline into the stream.
Line 19 is unformatted input. The first time probably returns an empty string.

Insert between lines 17 and 18:
cin.ignore( 1, '\n' );


If you want to read all input before showing any answers, then you have to store the answers rather than print immediately.

[reach devi]

@keskiverto Thank you very much.The code worked perfectly.And i thank cplusplus.com for providing such a forum.
I will be posting in this forum whenever i stuck in programming.