在处理字符串时,经常要察看字符串的长度,用 expr 可以简单地完成这个功能,在console命令行下: >expr 《your_string》: ".*" (return) 本文来自ChinaUnix博客,如果查看原文请点:http://blog.chinaunix.net/u1/45602/showart_389790.html
Can anyone write me a recursive function/algorithm to output a set of all strings which are the r-combinations of a string with length n?? Thanks.
环境:as4 + php5.1.1 +mysql 错误:提示:fatal error: Function name must be a string in 定义的代码: $db_query = "mysql_query"; $db_fetch_row = "mysql_fetch_row"; $db_fetch_array = "mysql_fetch_array"; $db_num_rows = "mysql_num_rows"; $db_insert_id = "mysql_insert_id"; $db_free_result = "mysql_free_result"; $db_link = $db_pconnect("$db_server","$db_server_user","$db_server_user_passw...
运行下面一行代码,连接数据库时候出错 报的错误是: Catchable fatal error: Object of class PDO could not be converted to string in /www/infomix.php on line 3
int testtest (int length) { std::vector< std::string> > text; std::string line(length,'c'); text.reserve(2000000 ); for(int i = 0 ; i<2000000; i++) text.push_back(line); } 上面程序只是一个简化的例子, 每次调用,push_back()的string长度永远的是一样的,由变量length决定。 但是由于数据量太大了,性能成为问题了。 现在想通过提前reserve 避免不必要的内存拷贝。 问题的关键是: 外层可以用reserve改...
[code]
string s="我";
cout<
warning: unsupported SASL server implementation: cyrus postfix/smtpd[13710]: fatal: SASL per-process initialization failed postfix/master[13575]: warning: process /usr/libexec/postfix/smtpd pid 13710 exit status 1 postfix/master[13575]: warning: /usr/libexec/postfix/smtpd: bad command startup -- throttling 请问什么原因啊? 谢谢