Timus 1601. AntiCAPS

Timus 1601. AntiCAPS 要求把一段大寫英文字母的文本轉換為適當的小寫英文字母。
1601. AntiCAPS

Time Limit: 0.5 second
Memory Limit: 64 MB

The blonde Angela has a new whim: internet chats. Of course, as any blonde, she
writes her messages using the upper case. You are the moderator of Angela's
favorite chat and you're fed up with her upper-case messages. The problem
is that Angela does not respond to your warnings. You decided to write a simple
antiCAPS corrector, which would make Angela's messages readable.

The correction rules are very simple:

1. Sentences in a message consist of words, spaces and punctuation marks.
2. Words consist of English letters.
3. Sentences end with a full stop, exclamation mark, or question mark.
4. The first word of each sentence must start with a capital letter, and all other
   letters of the sentence must be lowercase.

Input

You are given Angela's message, which consists of uppercase English letters,
spaces, line breaks and punctuation marks: full stops, commas, dashes, colons, exclamation
and question marks. Total length of message is not exceeding 10000 symbols.

Output

Output the corrected message.

Sample

input	output
HI THERE! HOW DID YOU KNOW I AM A BLONDE?	Hi there! How did you know i am a blonde?

Problem Author: Denis Musin
Problem Source: IX USU Open Personal Contest (March 1, 2008)

答案如下(C#語言)：

 1 using System;
 2 
 3 namespace Skyiv.Ben.Timus
 4 {
 5   sealed class T1601
 6   {
 7     static void Main()
 8     {
 9       int v;
10       bool isCap = true;
11       while ((v = Console.In.Read()) != -1)
12       {
13         char c = (char)v;
14         if (c == '.' || c == '!' || c == '?') isCap = true;
15         else if (isCap && char.IsUpper(c)) isCap = false;
16         else if (!isCap && char.IsUpper(c)) c = char.ToLower(c);
17         Console.Write(c);
18       }
19     }
20   }
21 }

下面是C語言的版本：

 1 #include <stdio.h>
 2 
 3 int main()
 4 {
 5   int c, isCap = 1;
 6   while ((c = getchar()) != EOF)
 7   {
 8     if (c == '.' || c == '!' || c == '?') isCap = 1;
 9     else if (isCap && isupper(c)) isCap = 0;
10     else if (!isCap && isupper(c)) c = tolower(c);
11     putchar(c);
12   }
13 }