#include <stdio.h>

int main(void)

{
    int index = 0, combinationTimes = 0, total = 0;
    char userInput;
    char wordChar[index];

    printf("please enter your input:n");

    while ((userInput = getchar()) != '#')
    {
        if (userInput == 'n')
            continue;

        wordChar[index] = userInput;
        index++;
        total++;
    }

    for (index = 1; index < total; index++)
    {
        if (wordChar[index] == 'i')
        {
            if (wordChar[--index] == 'e')
            {
            combinationTimes++;
            ++index;
            }
        }
    }

    printf("number of combination is: %d", combinationTimes);

    return 0;
}

dan@albatross  $ gcc -Wall f.c -o f
dan@albatross  $ ./f
please enter your input:
bfiqwb23b r9pu3h2ru23r
9aisdbfuiasdf
adsf#asdf
#
#
#
    adsfadsfasdf
34324!
^C

for (index = 1; index < total; index++)
    {
        if (wordChar[index] == 'i' && wordChar[index - 1] == 'e')
            combinationTimes++;
    }

#define FALSE 0
#define TRUE 1

int main(void)
{
    int combinationTimes = 0;
    char userInput;
    short int last_e = FALSE;

    printf("please enter your input:n");

    while ((userInput = getchar()) != '#')
    {
        if (userInput == 'e')
        {
            last_e = TRUE;
        }
        else if (userInput == 'i' && last_e)
        {
            combinationTimes++;
            last_e = FALSE;
        }
        else
        {
            //this is important, otherwise combinations like 'ite' are counted
            last_e = FALSE;
        }
    }

    printf("Number of combos: %dn", combinationTimes);
    return 0;
}