Playing with Requirements

#include <math.h>
#include <stdio.h>
#include <stdlib.h>

int checkDupe(int);
int checkSquare(int);
int checkZeros(int);

int main(void)
{
    int index;
    int counter = 0;

    for (index = 111111111; index < 1000000000; index++)
    {

        if ((checkZeros(index) == 1) && (checkSquare(index) == 1)
            && (checkDupe(index) == 1))
        {
            counter++;
            printf("%d. %d\n", counter, index);
        }

    }
}

int checkDupe(int number)
{
    char strNum[10];
    char charNum;
    int dupeArr[10];
    int numsPlace[10];
    int index, dupes = 0;
    int isValid = 1;

    //convert to a string
    for(index = 9; index >= 0; index--)
    {
        numsPlace[index] = number % 10;
        number = number / 10;
        strNum[index] = numsPlace[index] + 48;
    }

    //initialize the array. 10 = intArray.length
    for (index = 0; index < 10; index++)
    {
        dupeArr[index] = 0;
    }

    //count how many of each number are in the string
    for (index = 0; index < strlen(strNum); index++)
    {
        charNum = strNum[index];

        switch (charNum)
        {
            case '0':
                dupeArr[0]++;
                break;
            case '1':
                dupeArr[1]++;
                break;
            case '2':
                dupeArr[2]++;
                break;
            case '3':
                dupeArr[3]++;
                break;
            case '4':
                dupeArr[4]++;
                break;
            case '5':
                dupeArr[5]++;
                break;
            case '6':
                dupeArr[6]++;
                break;
            case '7':
                dupeArr[7]++;
                break;
            case '8':
                dupeArr[8]++;
                break;
            case '9':
                dupeArr[9]++;
                break;
            default:
                break;
        }
    }

    //If there is more than 1 in any place, it's a duplicate
    for (index = 0; index < 10; index++)
    {
        if (dupeArr[index] >= 2)
        {
            isValid = 0;
        }
    }

    return isValid;
}

int checkZeros(int number)
{
    char strNum[10];
    char charNum;
    int index;
    int numsPlace[9];
    int isValid = 1;

    //convert to a string
    for(index = 8; index >= 0; index--)
    {
        numsPlace[index] = number % 10;
        number = number / 10;
        strNum[index] = numsPlace[index] + 48;
    }

    //check if there are any zeros
    for (index = 0; index < 10; index++)
    {
        charNum = strNum[index];
        if (charNum == '0')
            isValid = 0;
    }

    return isValid;
}

int checkSquare(int number)
{
    int sqRoot = (int)sqrt(number);
    int isPerfect = 0;

    if ((sqRoot * sqRoot) == number)
        isPerfect = 1;
    else
        isPerfect = 0;

    return isPerfect;
}