removal of vowels from string in c code example

Example 1: remove vowels in string

#include <stdio.h>
int check_vowel(char);
int main()
{
char s[100], t[100];
int c, d = 0;
gets(s);
for(c = 0; s[c] != ‘\0’; c++)
{
if(check_vowel(s[c]) == 0)
{
t[d] = s[c];
d++;
}
}
t[d] = ‘\0’;
strcpy(s, t);
printf(“%s\n”, s);
return 0;
}
int check_vowel(char ch)
{
if (ch == ‘a’ || ch == ‘A’ || ch == ‘e’ || ch == ‘E’ || ch == ‘i’ || ch == ‘I’ || ch ==’o’ || ch==’O’ || ch == ‘u’ || ch == ‘U’)
return 1;
else
return 0;
}

Example 2: Remove all the vowels from a given string using pointers concept

#include<stdio.h>#include<stdlib.h>#include<string.h>#define TRUE 1#define FALSE 0 int check_vowel(char); main(){   char string[100], *temp, *pointer, ch, *start;    printf("Enter a string\n");   gets(string);    temp = string;   pointer = (char*)malloc(100);   if( pointer == NULL )   {      printf("Unable to allocate memory.\n");      exit(EXIT_FAILURE);   }    start = pointer;    while(*temp)   {      ch = *temp;       if ( !check_vowel(ch) )      {         *pointer = ch;         pointer++;      }      temp++;   }   *pointer = '\0';    pointer = start;   strcpy(string, pointer); /* If you wish to convert original string */   free(pointer);    printf("String after removing vowel is \"%s\"\n", string);    return 0;} int check_vowel(char a){   if ( a >= 'A' && a <= 'Z' )      a = a + 'a' - 'A';    if ( a == 'a' || a == 'e' || a == 'i' || a == 'o' || a == 'u')      return TRUE;    return FALSE;}