codeforce 5A Chat Server's Outgoing Traffic

A. Chat Server's Outgoing Traffic

time limit per test
1 second

memory limit per test
64 megabytes

input
standard input

output
standard output

Polycarp is working on a new project called "Polychat". Following modern tendencies in IT, he decided, that this project should contain chat as well. To achieve this goal, Polycarp has spent several hours in front of his laptop and implemented a chat server
that can process three types of commands:

Include a person to the chat ('Add' command).

Remove a person from the chat ('Remove' command).

Send a message from a person to all people, who are currently in the chat, including the one, who sends the message ('Send'command).

Now Polycarp wants to find out the amount of outgoing traffic that the server will produce while processing a particular set of commands.

Polycarp knows that chat server sends no traffic for 'Add' and 'Remove' commands. When 'Send' command is processed, server sends lbytes to each participant
of the chat, where l is the length of the message.

As Polycarp has no time, he is asking for your help in solving this problem.

Input

Input file will contain not more than 100 commands, each in its own line. No line will exceed 100 characters. Formats of the commands will be the following:

+<name> for 'Add' command.

-<name> for 'Remove' command.

<sender_name>:<message_text> for 'Send' command.

<name> and <sender_name> is a non-empty sequence of Latin letters
and digits. <message_text> can contain letters, digits and spaces, but can't start or end with a space. <message_text> can
be an empty line.

It is guaranteed, that input data are correct, i.e. there will be no 'Add' command if person with such a name is already in the chat, there will be no 'Remove' command
if there is no person with such a name in the chat etc.

All names are case-sensitive.

Output

Print a single number — answer to the problem.

意思就是说有一个服务器，支持三种命令，add，remove，send。分别是增加，删除和发送消息。

发送消息时，服务器会发出 L 字节的流量，L是消息的字符数。

三种命令格式分别如下：

+lwj

+xrc

-xrc

lwj:i love you

给定一系列的命令，求服务器所有发出的流量。保证输入add命令前该用户不在服务器上，remove命令前该用户一定在服务器上，即保证输入的合法性。

反正这就是一道水题，主要是注意输入的消息可能是包含空格的，所以得getline来读。

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>
#include <stack>
#include <map>
#include <queue>
#include <algorithm>
using namespace std;

int main() {

int num = 0, ans = 0;
string str;
char ctmp[105];
while (cin.getline(ctmp, 105)) {
str = ctmp;
if (str[0] == '+') {
num++;
} else if (str[0] == '-') {
num --;
} else {
ans += num * (str.length() - 1 - str.find(':'));
}
}
cout << ans << endl;
return 0;
}