Bucky's C Challenge #1

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <math.h>
/*Password Verification Program tests for 8 to 10 characters, and at least
 *1 upper case letter, 1 lower case letter, 1 digit, 1 '$' punctuation*/

int main()
{
    char userName[50];
    char firstPassword[100];
    char password[100];
    int a = 0;
    int upper = 0, lower = 0, digit = 0, dollarSign = 0;

    printf("Please Create A Username Without Spaces.\n\nNext Create A Password"
           "Between 8 & 10 Characters In Length.\nThe Password Must Include "
           "At Least One Upper Case Letter,\nOne Lower Case Letter, One Digit,"
           "and the '$' Punctuation.\n\n\n");

    printf("Enter Username:    ");
    scanf(" %s", userName);

//Prompts for firstPassword & password then compares strings until they match
    do {
        printf("\nEnter Password:    ");
        scanf(" %s", firstPassword);
        printf("Confirm Password:  ");
        scanf(" %s", password);

        if(strcmp(firstPassword, password) != 0)
            printf("\nPasswords Do Not Match, Try Again.\n\n");
    }while(strcmp(firstPassword, password) != 0);

//Tests for Upper/Lower/Digit/'$' and adds 1 to respective int variables
    while(a <= 10){
    if(isupper(password[a])) {
        upper = 1;
    }
    if(islower(password[a])) {
        lower = 1;
    }
    if(isdigit(password[a])) {
        digit = 1;
    }
    if((password[a] == '$')) {
        dollarSign = 1;
    }
    a++;
    }

/*Test password length 8 to 10 characters
 *Nested If-else tests for password requirements*/
    if (strlen(password) >= 8 && strlen(password) <= 10){
        if(upper && lower && digit && dollarSign){
            printf("\nCongratulations %s Your Password Is Set.\n", userName);
        }
    else{
        printf("\nTry Again, Your Password Needs At Least 1 Upper/Lower/Digit/'$':\n");
    }
    }
//Test password length - too long/short
    if(strlen(password) >= 11){
        printf("\nPassword Is Too Long. Maximum 10 Characters In Length. Try Again.\n\n");
    }
    if(strlen(password) <= 7){
        printf("\nPassword Is Too Short. Minimum 8 Characters In Length. Try Again.\n\n");
    }

return 0;
}