codeforces 424D Biathlon Track 题意 题解 代码 #include<bits/stdc++.h> using namespace std; #define fi first #define se second #define mp make_pair #define pb push_back #define rep(i, a, b) for(int i=(a); i<(b); i++) #define sz(a) (int)a.size() #define…

Codeforces Round #242 (Div. 2) D:http://codeforces.com/contest/424/problem/D 题意:给你一个n*m的矩阵,每个格子上面有个数字,在相邻格子之间会有一定的费用,费用根据相邻格子的大小关系确定.让你费用最接近一个数的矩阵. 题解:一看题目,想了一下,预处理,然后猜到要用二分.但是二维的怎么二分,一直没有想到什么办法,一直想的是(n*mlog(n*m))的算法,所以不对了.其实应该固定一个起点,作为矩阵的左上角的点,然后枚举右…

CF424 A. Squats 题目意思: 有n(n为偶数)个x和X,求最少的变换次数,使得X的个数为n/2,输出变换后的序列. 解题思路: 统计X的个数ans,和n/2比較,少了的话,须要把n/2-ans个x变成X,多了的话须要把ans-n/2个X变成x.(从前往后扫一遍即可了). 代码: //#include<CSpreadSheet.h> #include<iostream> #include<cmath> #include<cstdio> #incl…

"Track changes" is wonderful and remarkable tool of Microsoft Word 2010. The feature allows editing your documents without making the changes permanent. It means if you have deleted a word, Track back highlights it, though the word is deleted bu…

IEEE/ACM International Conference on Advances in Social Network Analysis and Mining (ASONAM) 2014 Industry Track Call for Papers * Apologies if you received multiple copies of this CFP * Beijing China August 17-20, 2014Home Page: www.asonam2014.org F…

我们见到最简单的例子是: <div ng-repeat="link in links" ></div> 如果item的值有重复的,比如links=["1","1","2","2","3"] 那么angularjs 会报错,不允许值重复,原因是angular需要一个唯一值可以与生成的dom绑定,以便追踪. 然后这时候,track by的用处就体现出来了. <d…

上一篇文章(http://www.cnblogs.com/yangdanny/p/4421130.html)我们解决了在FFmpeg下如何处理H264和AAC的扩展数据,根据解出的NALU长度恢复了H264的起始码和AAC的ADTS头,这样一般来说播放是没有问题.本篇文章来谈谈如何实现基于FFmpeg的track mode控制,也就是如何用FFmpeg提供的功能来实现基本的seek.快进.快退.好了,废话少了,下面开始基于FFmpeg的track mode之旅. FFmpeg提供了一个seek函…

错误原因在于出现相同内容. 原写为: <li ng-repeat="log in logs" scroll-down> {{log}}</li> 改写为: <li ng-repeat="log in logs track by $index" scroll-down> {{log}}</li> 加track by $index即可解决.…

ng-repeat指令中使用track by子语句解决重复数据遍历的错误 <li ng-repat="x in [2, 2]" ng-bind="x"></li> 是错误的,认为不能出现重复值(id) <li ng-repat="x in [2, 2] track by $id($index)" ng-bind="x"></li>…

angularjs 使用ng-repeat报错 <div ng-init="words = ['高校','高校','高校']" ng-repeat="word in words"> {{word}} </div> [ngRepeat:dupes] Duplicates in a repeater are not allowed. Use 'track by' expression to specify unique keys 发现是因为相同的…