/*This program makes all vowels uppercase.                         
  All other constants are lowercase.                               
  Keep in mind I make to call a function                           
  isvowel() to evluate the character.*/                            
 
#include <stdio.h>                                                 
#include <ctype.h>                                                 
 
int isvowel(int ch);                                               
 
int main(void)                                                     
{                                                                  
  int ch;                                                          
  while(ch=getchar()){                                             
    if(isvowel(ch)==1)                                             
      putchar(isupper(ch));                                        
    else                                                           
      putchar(islower(ch));                                        
  }     
  return 0;                                                 
}                                                           
int isvowel(int ch)                                         
{                                                           
  if(ch=='a' || ch=='e' || ch=='i' || ch=='o' || ch=='u')   
    return 1;                                               
}