CodeForces - 468A
Little X used to play a card game called "24 Game", but recently he has found it too easy. So he invented a new game.
Initially you have a sequence of n integers: 1, 2, ..., n. In a single step, you can pick two of them, let's denote them a and b, erase them from the sequence, and append to the sequence either a + b, or a - b, or a × b.
After n - 1 steps there is only one number left. Can you make this number equal to 24?
Input
The first line contains a single integer n (1 ≤ n ≤ 105).
Output
If it's possible, print "YES" in the first line. Otherwise, print "NO" (without the quotes).
If there is a way to obtain 24 as the result number, in the following n - 1 lines print the required operations an operation per line. Each operation should be in form: "a op b = c". Where a and b are the numbers you've picked at this operation; op is either "+", or "-", or "*"; c is the result of corresponding operation. Note, that the absolute value of c mustn't be greater than 1018. The result of the last operation must be equal to 24. Separate operator sign and equality sign from numbers with spaces.
If there are multiple valid answers, you may print any of them.
Examples
1
NO
8
YES
8 * 7 = 56
6 * 5 = 30
3 - 4 = -1
1 - 2 = -1
30 - -1 = 31
56 - 31 = 25
25 + -1 = 24 题目大意:给你一个n,1-n当中每次选两个数进行运算,进行n-1次运算后要为24,并且用过的数不能再用,新算出的数可以接着用,打印任意一种情况。 思路:n小于4的一定不可以,n等于4和5需要特判,其他情况都可以转化为3-2=1,1-1=0开头,然后用0*i=0(i!=4&&i!=6),最后加个4*6=24就行了。
代码:
#include<stdio.h>
#include<iostream>
#include<string.h>
using namespace std;
int main()
{
int n;
cin>>n;
if(n<)
cout<<"NO"<<endl;
else if(n==)
{
cout<<"YES"<<endl;
printf("1 * 2 = 2\n");
printf("2 * 3 = 6\n");
printf("4 * 6 = 24\n");
}
else if(n==)
{
cout<<"YES"<<endl;
printf("3 * 5 = 15\n");
printf("2 * 4 = 8\n");
printf("15 + 8 = 23\n");
printf("23 + 1 = 24\n");
}
else
{
cout<<"YES"<<endl;
printf("3 - 2 = 1\n");
printf("1 - 1 = 0\n");
printf("0 * 5 = 0\n");
for(int i=;i<=n;i++)
if(i!=&&i!=)
printf("0 * %d = 0\n",i);
printf("4 * 6 = 24\n");
printf("24 + 0 = 24\n");
}
return ;
}
CodeForces - 468A的更多相关文章
- codeforces 468A. 24 Game 解题报告
题目链接:http://codeforces.com/problemset/problem/468/A 题目意思:给出一个数n,利用 1 - n 这 n 个数,每个数只能用一次,能否通过3种运算: + ...
- CodeForces 468A Program F
Description Little X used to play a card game called "24 Game", but recently he has found ...
- [ An Ac a Day ^_^ ] CodeForces 468A 24 Game 构造
题意是让你用1到n的数构造24 看完题解感觉被样例骗了…… 很明显 n<4肯定不行 然后构造出来4 5的组成24的式子 把大于4(偶数)或者5(奇数)的数构造成i-(i-1)=1 之后就是无尽的 ...
- CodeForces - 468A ——(思维题)
Little X used to play a card game called "24 Game", but recently he has found it too easy. ...
- python爬虫学习(5) —— 扒一下codeforces题面
上一次我们拿学校的URP做了个小小的demo.... 其实我们还可以把每个学生的证件照爬下来做成一个证件照校花校草评比 另外也可以写一个物理实验自动选课... 但是出于多种原因,,还是绕开这些敏感话题 ...
- 【Codeforces 738D】Sea Battle(贪心)
http://codeforces.com/contest/738/problem/D Galya is playing one-dimensional Sea Battle on a 1 × n g ...
- 【Codeforces 738C】Road to Cinema
http://codeforces.com/contest/738/problem/C Vasya is currently at a car rental service, and he wants ...
- 【Codeforces 738A】Interview with Oleg
http://codeforces.com/contest/738/problem/A Polycarp has interviewed Oleg and has written the interv ...
- CodeForces - 662A Gambling Nim
http://codeforces.com/problemset/problem/662/A 题目大意: 给定n(n <= 500000)张卡片,每张卡片的两个面都写有数字,每个面都有0.5的概 ...
随机推荐
- Git&Version Control
Git Git(读音为/gɪt/.)是一个开源的分布式版本控制系统,可以有效.高速地处理从很小到非常大的项目版本管理. [1] Git 是 Linus Torvalds 为了帮助管理 Linux 内 ...
- LeetCode 705 Design HashSet 解题报告
题目要求 Design a HashSet without using any built-in hash table libraries. To be specific, your design s ...
- 在vue中使用lang="scss"出现报错解决思路
最近在学习vue框架,使用lang="scss" 出现如下错误: This dependency was not found: * !!vue-style-loader!css-l ...
- SQL中ON和WHERE的区别(转)
原文:https://www.cnblogs.com/guanshan/articles/guan062.html 数据库在通过连接两张或多张表来返回记录时,都会生成一张中间的临时表,然后再将这张临时 ...
- nginx修改上传文件大小限制
问题: 项目上线,图片上传报413错误,找了半天,原来是nginx限制了上传大小 在nginx.conf的server的location中加client_max_body_size 10m;
- pc端字体大小计算以及echart中字体大小计算
<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8" ...
- 使用@Autowired时,取值为null
如果取不到,可以考虑其他方式 场景: @Autowired private StringRedisTemplate redisTemplate; 想使用redisTemplate,但是使用时为null ...
- 多个页面引用公共的头部 header.html 和尾部 footer.html
方法:通过load()函数,引入公共头部和尾部文件; js代码预览: $(".headerPage").load("header.html"); $(" ...
- windows----------windows10如何固定局域网ip
1. 2. 3. 4. 5.
- 自动化运维工具——ansile详解
自动化运维工具——ansible详解(一) 目录 ansible 简介 ansible 是什么? ansible 特点 ansible 架构图 ansible 任务执行 ansible 任务执行模式 ...