https://code.google.com/codejam/contest/204113/dashboard 题目大意: 给你一个矩阵,让你转化为下三角矩阵,每次只能交换相邻的行,求最小的交换次数. 思路: 一开始觉得记录每一行最后一个1的位置,然后相邻交换排序可以直接冒泡法(甚至可以nlogn的合并排序),结果交上去错的. 想了想因为每一行最后一个1已经满足j<=i了,所以..(设行i列j) 那么就只好贪心啦,每次选最近的要交换的. #include<cstdio> #includ…

Google Code Jam 2010 Round 1C Problem A. Rope Intranet https://code.google.com/codejam/contest/619102/dashboard#s=p0 Problem A. Rope Intranet A company is located in two very tall buildings. The company intranet connecting the buildings consists of m…

题意: 给定一个N*N的矩阵,由0,1组成,只允许交换相邻的两行,把矩阵转化为下三角矩阵(对角线上方全是0),最少需要多少次交换?(保证可以转化为下三角矩阵) Large: N<=40 解析: 假如每一行的1的个数都是不相同的,即,最终答案中的矩阵是唯一的,这就相当于求对给定数组冒泡排序需要几次交换一样.但显然,题目没有如此保证. 方法是贪心法:(策略不给出证明) 从第一行到最后一行依次满足,因为可以满足前面行的也一定可以满足后面的,所以每次只需要找到可以满足当前行的最近的就可以了. 预处理最后…

Problem You are given an N x N matrix with 0 and 1 values. You can swap any two adjacent rows of the matrix. Your goal is to have all the 1 values in the matrix below or on the main diagonal. That is, for each X where 1 ≤ X ≤ N, there must be no 1 va…

https://code.google.com/codejam/contest/635101/dashboard#s=p0   Problem On Unix computers, data is stored in directories. There is one root directory, and this might have several directories contained inside of it, each with different names. These di…

Problem You are given an N x N matrix with 0 and 1 values. You can swap any two adjacent rows of the matrix. Your goal is to have all the 1 values in the matrix below or on the main diagonal. That is, for each X where 1 ≤ X ≤ N, there must be no 1 va…

Problem B. Infinite House of Pancakes Problem's Link:   https://code.google.com/codejam/contest/6224486/dashboard#s=p1 Mean: 有无限多个盘子,其中有n个盘子里面放有饼,每分钟你可以选择两种操作中的一种: 1.n个盘子里面的饼同时减少1: 2.选择一个盘子里面的饼,分到其他盘子里面去: 目标是让盘子里的饼在最少的分钟数内吃完,问最少的分钟数. analyse: 可以分析出,先…

Problem A. Standing Ovation Problem's Link:   https://code.google.com/codejam/contest/6224486/dashboard#s=p0 Mean: 题目说的是有许多观众,每个观众有一定的羞涩值,只有现场站起来鼓掌的人数达到该值才会站起来鼓掌,问最少添加多少羞涩值任意的人,才能使所有人都站起来鼓掌. analyse: 贪心模拟一下,从前往后扫一遍就行. Time complexity: O(n) Source cod…

https://code.google.com/codejam/contest/544101/dashboard#s=p0     Problem In the exciting game of Join-K, red and blue pieces are dropped into an N-by-N table. The table stands up vertically so that pieces drop down to the bottom-most empty slots in…

https://code.google.com/codejam/contest/635101/dashboard#s=p1   Problem A flock of chickens are running east along a straight, narrow road. Each one is running with its own constant speed. Whenever a chick catches up to the one in front of it, it has…