https://blog.youkuaiyun.com/m0_62789921zh-cnhttps://blog.youkuaiyun.com/https://blog.youkuaiyun.com/m0_62789921/article/details/134645548https://blog.youkuaiyun.com/m0_62789921/article/details/134645548m0_62789921Mon, 27 Nov 2023 17:27:49 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/133299862https://blog.youkuaiyun.com/m0_62789921/article/details/133299862m0_62789921Tue, 26 Sep 2023 12:03:15 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/132617932https://blog.youkuaiyun.com/m0_62789921/article/details/132617932m0_62789921Fri, 01 Sep 2023 11:06:52 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/132583953https://blog.youkuaiyun.com/m0_62789921/article/details/132583953m0_62789921Wed, 30 Aug 2023 15:54:20 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/132499304https://blog.youkuaiyun.com/m0_62789921/article/details/132499304m0_62789921Sat, 26 Aug 2023 00:10:09 +0800 全表扫描（效率低）L:在访问巨值的限制查询，需要将0-巨量数据尾进行排列，取对应的限制区间，耗时长效率低。表（段（区（页（行））））一个区固定1m；B树：所有节点都会保存数据，导致一层可以查找的数据量少，同量数据B数的层级比B+树多。若通过索引进行事务update，不同行间相互隔离，可以提交（上。含义：存储数据、建立索引、更新/查询数据的实现方式。隔离级别越高：并发性能越差，数据安全性最高。数据页分裂（50%页移植到新页，再插入））：锁住数据库全部的表，[ 实例变成。]]>https://blog.youkuaiyun.com/m0_62789921/article/details/132287965https://blog.youkuaiyun.com/m0_62789921/article/details/132287965m0_62789921Mon, 14 Aug 2023 23:22:05 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/132285681https://blog.youkuaiyun.com/m0_62789921/article/details/132285681m0_62789921Mon, 14 Aug 2023 23:01:17 +0800 7不会变，在静态变量区，可以取到地址 -> 编译成功。int &x = 7 -> 由于7为临时变量，故x取不到临时变量的地址-> 编译出错。int &&x = 7 -> 右值引用（万能引用）相当于。int &x = i；常量左值引用即可接受左值也可接受右值。通常字面量都是右值，但。]]>https://blog.youkuaiyun.com/m0_62789921/article/details/132207044https://blog.youkuaiyun.com/m0_62789921/article/details/132207044m0_62789921Thu, 10 Aug 2023 12:45:01 +0800>num;// 从 is 流中读入一个 int 整数存入 num 中// 构造一个输出字符串流，流内容为空os << num;// 向输出字符串流中输出 num 的内容// 利用字符串流的 str 函数获取流中的内容字符串流对象的 str 函数对于 istringstream 和 ostringstream 都适用，都可以获取流中的内容。]]>https://blog.youkuaiyun.com/m0_62789921/article/details/132168814https://blog.youkuaiyun.com/m0_62789921/article/details/132168814m0_62789921Tue, 08 Aug 2023 22:03:12 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/132056821https://blog.youkuaiyun.com/m0_62789921/article/details/132056821m0_62789921Wed, 02 Aug 2023 16:18:47 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131682336https://blog.youkuaiyun.com/m0_62789921/article/details/131682336m0_62789921Sun, 30 Jul 2023 21:45:17 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131897585https://blog.youkuaiyun.com/m0_62789921/article/details/131897585m0_62789921Tue, 25 Jul 2023 11:26:12 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131819431https://blog.youkuaiyun.com/m0_62789921/article/details/131819431m0_62789921Wed, 19 Jul 2023 23:31:18 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131815782https://blog.youkuaiyun.com/m0_62789921/article/details/131815782m0_62789921Wed, 19 Jul 2023 19:31:32 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131787762https://blog.youkuaiyun.com/m0_62789921/article/details/131787762m0_62789921Tue, 18 Jul 2023 16:38:54 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/131765478https://blog.youkuaiyun.com/m0_62789921/article/details/131765478m0_62789921Tue, 18 Jul 2023 11:43:28 +0800 128k -> 调用mmap()），后调用brk（）函数。采用内存池管理方式：申请大块内存作为堆区，并分为多个内存块。用户申请时分配空闲块，采用隐式链表记录空闲连续的内存地址 使用场景 别人库调用我们的函数，称回调函数（callback）。 野指针： 定义：释放内存后，没有置NULL（指向地址不可知）的指针避免方法: 1)初始换置NULL ;2)申请内存判空 ;3)指针释放后置NULL ;4)智能指针（自动释放内存）编译时]]>https://blog.youkuaiyun.com/m0_62789921/article/details/131717662https://blog.youkuaiyun.com/m0_62789921/article/details/131717662m0_62789921Fri, 14 Jul 2023 22:32:10 +0800= 最小单品质量（weight [ 0 ]）时，赋予价值总和为value[0]a. 背包总质量为0，dp[i][0] 必为 0。]]>https://blog.youkuaiyun.com/m0_62789921/article/details/131704823https://blog.youkuaiyun.com/m0_62789921/article/details/131704823m0_62789921Thu, 13 Jul 2023 20:22:33 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/130886513https://blog.youkuaiyun.com/m0_62789921/article/details/130886513m0_62789921Fri, 26 May 2023 21:16:27 +0800https://blog.youkuaiyun.com/m0_62789921/article/details/130855960https://blog.youkuaiyun.com/m0_62789921/article/details/130855960m0_62789921Thu, 25 May 2023 23:49:45 +0800