Question

I have a list, it’s already sorted in alphabetical order. I’d like to break it into sections corresponding with the letter is starts with, like so:

A

• aListItem1
• aListItem2
• aListItem3

B

• bListItem1
• bListItem2
• bListItem3

C

• cListItem1
• cListItem2
• cListItem3

…

I could do something like:

foreach item in list
if item startsWith A
… do something
if item startsWith B
… do something
if item startsWith C
… do something

etc…

but is there a more concise way to do this?

Answer 1

Just keep track of the current first letter as you go:

char first = '\0';
foreach(string item in list){
     if(item[0] != first){
         first = item[0];
         Console.WriteLine(first);
     }

     Console.WriteLine("  *  " + item);
}