Print out put like this

int main(int argc, char *argv[])
{
    char* word = "12345";
    
    int start  = 0;
    int finish = strlen(word);
    int direction = 1;
    int i = 0;
    
    while (start < finish) {
        if (direction == 1) {
            finish--;
            for (i = start ; i <= finish ; i++)
                printf("%c" , word[i]);
        }
        else {
            start++;
            for (i = finish ; i >= start ; i--)
                printf("%c" , word[i]);
        }
        direction=-direction;
        
        printf("\r");
        getchar();        
    }
    return 0;
}