Pig-Latin (UVA492)

You have decided that PGP encryptation is not strong enough for your
email. You have decided to supplement it by first converting your
clear text letter into Pig Latin before encrypting it with PGP.

Input and Output

You are to write a program that will take in an arbitrary number of
lines of text and output it in Pig Latin. Each line of text will
contain one or more words. A “word” is defined as a consecutive
sequence of letters (upper and/or lower case). Words should be
converted to Pig Latin according to the following rules (non-words
should be output exactly as they appear in the input):

1. Words that begin with a vowel (a, e, i, o, or u, and the capital versions of these) should just have the string “ay” (not including the
   quotes) appended to it. For example, “apple” becomes “appleay”.
2. Words that begin with a consonant (any letter than is not A, a, E, e, I, i, O, o, U or u) should have the first consonant removed and
   appended to the end of the word, and then appending “ay” as well. For
   example, “hello” becomes “ellohay”.
3. Do not change the case of any letter.

Sample Input

This is the input.

Sample Output

hisTay isay hetay inputay.

/* General idea ：  Judge the input string character by character ; */ 
#include<iostream>
#include<string>
using namespace std;
// Decide if it's a letter 
int isab(char ch){
    		 
	if((ch>='a'&&ch<='z')||(ch>='A'&&ch<='Z'))
		return 1;
	else 
		return 0;
}
// Determine if it's a vowel  
int vowel(char ch){
    		
	if(ch=='a'||ch=='e'||ch=='i'||ch=='o'||ch=='u'
		||ch=='A'||ch=='E'||ch=='I'||ch=='O'||ch=='U')
		return 1;
	else 
		return 0;
}
int main(){
    
	string str;
	getline(cin,str);
	char temp;
	int flag=0;	//flag Used to mark whether a character is within a word  
	for(int i=0;i<str.size();i++){
    
		// This character is not a letter , but  flag==1, Explain that a word is over . 
		if(!isab(str[i])&&flag==1){
    
			if(isab(temp))
				cout<<temp;
			cout<<"ay";
			cout<<str[i];
			temp='@';
			flag=0;
		}
		// Other characters not next to words , Then output directly  
		else if(!isab(str[i]))
			cout<<str[i];
		//flag==0, It's a vowel letter , It is a word that begins with a vowel  
		else if(vowel(str[i])&&flag==0){
    
			cout<<str[i];
			flag=1;
		}
		//  Empathy , But consonants begin , Deposit first temp, Output the rest of the characters of the whole word after it is finished （ The first 31 That's ok ） 
		else if(!vowel(str[i])&&flag==0){
    
			temp=str[i];
			flag=1;
		}
		// The characters inside the word can be output directly  
		else 
			cout<<str[i];
	}
	cout<<endl;
}