def valid_passwords_1(passwords):
    """
    Takes a list of password strings, and returns the number of passwords in 
    the list meeting the following criteria:
        
        - Passwords are six digit numbers
        - In each password two adjacent digits must be the same
        - In each password, going from largest to smallest digit, the size of
        the digit does not decrease:
            111123, 135679, 111111 meet the criteria
            223450 does not (decreasing pair of digits 50)
            123789 does not (no double adjacent digits)  
    """
    
    valid = 0
    
    for entry in passwords:
        adjacent = False
        order = True
        
        #Check for adjacent duplicate numbers
        for i in range(len(entry) - 1):
            
            if entry[i] == entry[i+1]:
                adjacent = True
                
        
        for i in range(len(entry) - 1):
            
            if entry[i] > entry[i+1]:
                order = False
                
        if adjacent and order:
            valid += 1
            
    return valid