2.6 KiB
Planning Number Words
Before you start programming, do some planning here on how you will break down this problem. Here's a hint: if you start by writing functions for smaller numbers, you will find that these functions help you with the larger numbers. For each of the cases below, explain how you would turn a number into a string. Feel free to write in sentences or in pseudocode (pseudocode is a sort of "casual programming" where you're almost writing in code, being pretty specific without worrying about syntax. For each case below, assume the integer is zero or more--don't worry about negative integers.
Integers under 10
(This one is done for you!) For an integer less than ten, you need to know the name of each digit, and look it up. You could use a big if/else statement like:
if number == 0:
return "zero"
elif number == 1:
return "one"
elif number == 1:
return "two"
A cleaner way to do this would be to make a list of digit names, from zero to nine. Then you could just look up a digit's name:
digit_names = [
"zero", "one", "two", "three", "four",
"five", "six", "seven", "eight", "nine"
]
return digit_names[number]
Integers under 20
If the integer is under 10, then use the procedure described above. Otherwise, ... (this is where you take over!) digit_names2 = [ "ten", "eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen" ] to get the digit, we devide the number by 10, and consider the remainder. return dignt_names2 [number%10]
Integers under 100
If the integer is under 20, use the previous procedure. Otherwise, for the numbers from 20 to 99, we do this. digit_names3 = [ "twenty", "thirty" , ....... "eighty", "ninety" ] We take first digit, get the name from the digit_names3. Digit 1 = digit_names3 [number//10-2] add hypen and add digit names [number%10]if the second digit is not zero. Else, add nothing.
Integers under 1000
Digit 1 = digit_names [number//100] add "hundred" R1 = number%100 If R1 is not zero, we add "and", then we call Integers under 100 procedure on R1.
Integers under 1000000
Q1 = number//1000 We call Intergers under 1000 procedure on Q1 We add "thousand" R1 = number%1000 If R1 is not zero, we call Integers under 1000 procedure on R1
Negative integers down to -1 million
We won't deal with negative integers in this problem set, but how would you deal with a negative integer, using the functions above? Number multiped by negative 1, we treat it as a new number. We call the same function as before (now it's positive number) We write "negative" in the begining of the answer.