1104 Sum of Number Segments

本文探讨了一个数学上的有趣现象——6174数字黑洞。通过一系列算法操作,任意一个四位数最终都会收敛到神秘的6174。文章详细解析了这一过程的实现方法,并提供了完整的代码示例。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

在这里插入图片描述在这里插入图片描述

题目大意:

给定任意一个各位数字不完全相同的四位正整数,如果先把四个数字按照非递增顺序再按照非递减顺序排序,所得到的两个数做差然后对差重复进行这一个操作,最后会停止在6174上,现在给你一个数模拟这个过程

解题思路:

因为数字只有四位,所以开一个数组分别保存每一位,然后模拟题意即可。
代码如下:

#include<iostream>
#include<cstdio>
#include<fstream>
#include<set>
#include<cmath>
#include<cstring>
#include<string>
#include<map>
#include<vector>
#include<iomanip>
#include<cstdlib>
#include<list>
#include<queue>
#include<stack>
#include<algorithm>
#define inf 0x3f3f3f3f
#define MOD 1000000007
#define mem0(a) memset(a,0,sizeof(a))
#define mem1(a) memset(a,-1,sizeof(a))
#define meminf(a) memset(a,inf,sizeof(a))
//vector ::iterator it;
//set<int>::iterator iter;
typedef long long ll;
typedef unsigned long long ull;
using namespace std;
int cmp(int a,int b)
{
  return a>b;
}
int main()
{
  int a[4],b[4],t;
  bool flag=false;
  cin>>t;
  while(t)//
  {
    a[0]=t%10;a[1]=t/10%10;a[2]=t/100%10;a[3]=t/1000;//保存从低到高的四位
    b[0]=t%10;b[1]=t/10%10;b[2]=t/100%10;b[3]=t/1000;//保存从高到低的四位
    sort(b,b+4,cmp);
    sort(a,a+4);
    int t2=b[0]*1000+b[1]*100+b[2]*10+b[3];
    int t1=a[0]*1000+a[1]*100+a[2]*10+a[3];
    t=t2-t1;
    cout<<setw(4)<<setfill('0')<<t2<<" - "<<setw(4)<<setfill('0')<<t1<<" = "<<setw(4)<<setfill('0')<<t<<endl;//控制字段长度
    flag=true;
    if(t==6174)return 0;//跳出死循环
  }
  if(!flag)//特判0
  cout<<"0000 - 0000 = 0000"<<endl;
//  std::ios::sync_with_stdio(false);
//  cin.tie(0);
//  freopen("test.txt","r",stdin);
//  freopen("output.txt","w",stdout);
 return 0;
}

Yousef has an array a of size n . He wants to partition the array into one or more contiguous segments such that each element ai belongs to exactly one segment. A partition is called cool if, for every segment bj , all elements in bj also appear in bj+1 (if it exists). That is, every element in a segment must also be present in the segment following it. For example, if a=[1,2,2,3,1,5] , a cool partition Yousef can make is b1=[1,2] , b2=[2,3,1,5] . This is a cool partition because every element in b1 (which are 1 and 2 ) also appears in b2 . In contrast, b1=[1,2,2] , b2=[3,1,5] is not a cool partition, since 2 appears in b1 but not in b2 . Note that after partitioning the array, you do not change the order of the segments. Also, note that if an element appears several times in some segment bj , it only needs to appear at least once in bj+1 . Your task is to help Yousef by finding the maximum number of segments that make a cool partition. Input The first line of the input contains integer t (1≤t≤104 ) — the number of test cases. The first line of each test case contains an integer n (1≤n≤2⋅105 ) — the size of the array. The second line of each test case contains n integers a1,a2,…,an (1≤ai≤n ) — the elements of the array. It is guaranteed that the sum of n over all test cases doesn't exceed 2⋅105 . Output For each test case, print one integer — the maximum number of segments that make a cool partition. Example InputCopy 8 6 1 2 2 3 1 5 8 1 2 1 3 2 1 3 2 5 5 4 3 2 1 10 5 8 7 5 8 5 7 8 10 9 3 1 2 2 9 3 3 1 4 3 2 4 1 2 6 4 5 4 5 6 4 8 1 2 1 2 1 2 1 2 OutputCopy 2 3 1 3 1 3 3 4 Note The first test case is explained in the statement. We can partition it into b1=[1,2] , b2=[2,3,1,5] . It can be shown there is no other partition with more segments. In the second test case, we can partition the array into b1=[1,2] , b2=[1,3,2] , b3=[1,3,2] . The maximum number of segments is 3 . In the third test case, the only partition we can make is b1=[5,4,3,2,1]
最新发布
06-09
评论
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值