POJ 1951 Extra Krunch G++

#include <iostream>
#include <cstring>
//谢谢博友文章 
using namespace std;
int main()
{
	string str;
	getline(cin,str);
	int hash[26];
	memset(hash,0,sizeof(hash));
	hash['A'-'A']=-1;
	hash['E'-'A']=-1;
	hash['I'-'A']=-1;
	hash['O'-'A']=-1;
	hash['U'-'A']=-1;
	int flag=0;//第一个字母不是空格 
	int kg=0;
	for(int i=0;i<str.size();i++)
	{
		if((str[i]>='A')&&(str[i]<='Z'))
		{
			if(hash[str[i]-'A']==0)
			{
				if(kg==1)
				{
					cout<<" ";
					kg=0;
				}
				cout<<str[i];
				hash[str[i]-'A']=1;
				flag=1;
			}
		}else if((str[i]==' ')&&(flag==1))
		{
			if((str[i+1]=='.')||(str[i+1]==',')||(str[i+1]=='?'))
			{
				
			}else
			{
				kg=1;
			}
		}else if((str[i]=='.')||(str[i]==',')||(str[i]=='?'))
		{
			cout<<str[i];
		}	
	}
	return 0;
}