Write a C program to find total number of vowels and consonants in a string.

/**
 * C program to count total number of vowel or consonant in a string using switch case
 */

#include <stdio.h>
#include <string.h>
#define MAX_SIZE 100 // Maximum string size

int main()
{
    char str[MAX_SIZE]; 
    int i, len, vowel, consonant;

    /* Input strings from user */
    printf("Enter any string: ");
    gets(str);


    vowel = 0;
    consonant = 0;
    len = strlen(str);

    for(i=0; i<len; i++)
    {
        if((str[i]>='a' && str[i]<='z') || (str[i]>='A' && str[i]<='Z'))
        {
            switch(str[i])
            {
                case 'a':
                case 'e':
                case 'i':
                case 'o':
                case 'u':
                case 'A':
                case 'E':
                case 'I':
                case 'O':
                case 'U':
                    vowel++;
                    break;
               ....

Without using pointers:

/**
 * C program to count total number of vowel or consonant in a string using switch case
 */

#include 
#include 
#define MAX_SIZE 100 // Maximum string size

int main()
{
    char str[MAX_SIZE]; 
    int i, len, vowel, consonant;

    /* Input strings from user */
    printf("Enter any string: ");
    gets(str);


    vowel = 0;
    consonant = 0;
    len = strlen(str);

    for(i=0; i='a' && str[i]<='z') || (str[i]>='A' && str[i]<='Z'))
        {
            switch(str[i])
            {
                case 'a':
                case 'e':
                case 'i':
                case 'o':
                case 'u':
                case 'A':
                case 'E':
                case 'I':
                case 'O':
                case 'U':
                    vowel++;
                    break;
                default:
                    consonant++;
            }
        }
    }

    printf("Total number of vowel = %d\n", vowel);
    printf("Total number of consonant = %d\n", consonant);

    return 0;
}

Using Pointers:

/**
 * C program to count total number of vowel or consonant in a string using pointers
 */

#include 
#include 
#define MAX_SIZE 100 // Maximum string size

int main()
{
    char str[MAX_SIZE]; 
    char * s = str;
    int vowel, consonant;

    /* Input strings from user */
    printf("Enter any string: ");
    gets(str);

    vowel = 0;
    consonant = 0;

    while(*s)
    {
        if((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <='Z'))
        {
            switch(*s)
            {
                case 'a':
                case 'e':
                case 'i':
                case 'o':
                case 'u':
                case 'A':
                case 'E':
                case 'I':
                case 'O':
                case 'U':
                    vowel++;
                    break;
                default:
                    consonant++;
            }
        }
        s++;
    }

    printf("Total number of vowel = %d\n", vowel);
    printf("Total number of consonant = %d\n", consonant);

    return 0;
}