Stars--树状数组
2016-03-17 09:07
351 查看
Stars
Description
Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given star. Astronomers want to know
the distribution of the levels of the stars.
For example, look at the map shown on the figure above. Level of the star number 5 is equal to 3 (it's formed by three stars with a numbers 1, 2 and 4). And the levels of the stars numbered by 2 and 4 are 1. At this map there are only one star of the level
0, two stars of the level 1, one star of the level 2, and one star of the level 3.
You are to write a program that will count the amounts of the stars of each level on a given map.
Input
The first line of the input file contains a number of stars N (1<=N<=15000). The following N lines describe coordinates of stars (two integers X and Y per line separated by a space, 0<=X,Y<=32000). There can be only one star at one point of the plane. Stars
are listed in ascending order of Y coordinate. Stars with equal Y coordinates are listed in ascending order of X coordinate.
Output
The output should contain N lines, one number per line. The first line contains amount of stars of the level 0, the second does amount of stars of the level 1 and so on, the last line contains amount of stars of the level N-1.
Sample Input
Sample Output
Time Limit: 1000MS | Memory Limit: 65536K | |
Total Submissions: 39882 | Accepted: 17303 |
Astronomers often examine star maps where stars are represented by points on a plane and each star has Cartesian coordinates. Let the level of a star be an amount of the stars that are not higher and not to the right of the given star. Astronomers want to know
the distribution of the levels of the stars.
For example, look at the map shown on the figure above. Level of the star number 5 is equal to 3 (it's formed by three stars with a numbers 1, 2 and 4). And the levels of the stars numbered by 2 and 4 are 1. At this map there are only one star of the level
0, two stars of the level 1, one star of the level 2, and one star of the level 3.
You are to write a program that will count the amounts of the stars of each level on a given map.
Input
The first line of the input file contains a number of stars N (1<=N<=15000). The following N lines describe coordinates of stars (two integers X and Y per line separated by a space, 0<=X,Y<=32000). There can be only one star at one point of the plane. Stars
are listed in ascending order of Y coordinate. Stars with equal Y coordinates are listed in ascending order of X coordinate.
Output
The output should contain N lines, one number per line. The first line contains amount of stars of the level 0, the second does amount of stars of the level 1 and so on, the last line contains amount of stars of the level N-1.
Sample Input
5 1 1 5 1 7 1 3 3 5 5
Sample Output
1 2 1 1 0 题意: 就是求某一颗星星的的最下方的星星的个数,等级为0---N-1 这道题就是利用树状数组求某一等级星星的个数 代码:# include <iostream> # include <cstdio> # include <cstring> using namespace std; int c[32003];//树状数组 int ans[15006];//保存等级 int bitlow(int x){ return x&-x; } int sum(int x){ int ans = 0; while(x>0){ ans+=c[x]; x-=bitlow(x); } return ans; } void modify(int x,int d){ while(x<32003){ c[x]+=d; x+=bitlow(x); } } int main(){ int n; int x,y; while(scanf("%d",&n)!=EOF){ memset(c,0,sizeof(c)); memset(ans,0,sizeof(ans)); for(int i=0;i<n;i++){ scanf("%d%d",&x,&y); ++x;//防止0 ans[sum(x)]++; //这里通过树状数组来计算等级为某一个值 仔细理解下 modify(x,1); } for(int i=0;i<n;i++){ printf("%d\n",ans[i]); } } return 0; }
相关文章推荐
- 安卓入门学习之Hello,world!
- 卸载IE9,IE10,IE11
- 删除提示找不到该项目的文件_20160317
- NSMutableAttributedString初探
- 第三周项目三输出星号图
- 第三周训练 本月有几天
- IOS 杂笔-3 (property参数)
- Java序列化与JSON序列化大比拼
- SIT与UAT的分别
- 第三周项目二-本月有几天
- 吾日三省吾身
- 从背景差分到深度学习方法的目标检测与前背景分离
- 移动图标
- 开博初记
- form表单填写,enter键实现tab键的下一个input获得焦点实现
- XMLHttpRequest Level 2 使用指南
- exchange 2010 证书
- poj1128(拓扑排序)
- STM32F10x系列的MCU配置PB3和PB4为普通IO口
- 2015 深度学习文章整理