zoukankan      html  css  js  c++  java
  • Educational Codeforces Round 42D. Merge Equals(STL)

    D. Merge Equals
    time limit per test
    2 seconds
    memory limit per test
    256 megabytes
    input
    standard input
    output
    standard output

    You are given an array of positive integers. While there are at least two equal elements, we will perform the following operation. We choose the smallest value xx that occurs in the array 22 or more times. Take the first two occurrences of xx in this array (the two leftmost occurrences). Remove the left of these two occurrences, and the right one is replaced by the sum of this two values (that is, 2x2⋅x).

    Determine how the array will look after described operations are performed.

    For example, consider the given array looks like [3,4,1,2,2,1,1][3,4,1,2,2,1,1]. It will be changed in the following way: [3,4,1,2,2,1,1]  [3,4,2,2,2,1]  [3,4,4,2,1]  [3,8,2,1][3,4,1,2,2,1,1] → [3,4,2,2,2,1] → [3,4,4,2,1] → [3,8,2,1].

    If the given array is look like [1,1,3,1,1][1,1,3,1,1] it will be changed in the following way: [1,1,3,1,1]  [2,3,1,1]  [2,3,2]  [3,4][1,1,3,1,1] → [2,3,1,1] → [2,3,2] → [3,4].

    Input

    The first line contains a single integer nn (2n1500002≤n≤150000) — the number of elements in the array.

    The second line contains a sequence from nn elements a1,a2,,ana1,a2,…,an (1ai1091≤ai≤109) — the elements of the array.

    Output

    In the first line print an integer kk — the number of elements in the array after all the performed operations. In the second line print kkintegers — the elements of the array after all the performed operations.

    Examples
    input
    Copy
    7
    3 4 1 2 2 1 1
    output
    Copy
    4
    3 8 2 1
    input
    Copy
    5
    1 1 3 1 1
    output
    Copy
    2
    3 4
    input
    Copy
    5
    10 40 20 50 30
    output
    Copy
    5
    10 40 20 50 30
    Note

    The first two examples were considered in the statement.

    In the third example all integers in the given array are distinct, so it will not change.

    题意:给出n个数,接下来对这个数列进行一个操作,即从左往右找最小的两个相同的数,然后将左边那个删除,右边那个数的值乘以2。不断进行以上操作,直到无相同的数为止,输出最终那个数列。

    思路:

    map中套一个set的操作,mp[i]指的是值为i的数字的下标合集。从小到大的遍历mp,如果有两个,则将其合并为一个放到2*i的集合中去。如果仅含一个元素,记录其的位置即可。

    代码:

     1 #include <bits/stdc++.h>
     2 
     3 using namespace std;
     4 typedef long long ll;
     5 const int maxn = 2e6+100;
     6 ll n;
     7 ll a[maxn];
     8 map<ll, set<ll> >mp;
     9 ll b[maxn];
    10 int main()
    11 {
    12     scanf("%I64d",&n);
    13     for(int i=1;i<=n;i++)
    14     {
    15         scanf("%I64d",&a[i]);
    16         mp[a[i]].insert((ll)i);
    17     }
    18     ll ans=0;
    19     for (auto it: mp)
    20     {
    21         while(it.second.size()>=2)
    22         {
    23             it.second.erase(it.second.begin());
    24             mp[it.first*2].insert(*it.second.begin());
    25             it.second.erase(it.second.begin());
    26         }
    27         if(it.second.size()==1)
    28         {
    29             int id=*it.second.begin();
    30             b[id]=it.first;
    31             ans++;
    32         }
    33     }
    34     printf("%I64d
    ",ans);
    35     for(int i=1;i<=n;i++) if(b[i]>0) printf("%I64d ",b[i]);
    36     return 0;
    37 }
  • 相关阅读:
    Org4的約會的Form_Load
    MSCRM 4 Remove 'Add Existing xxxxx to this record' button
    出售剩余时间
    MSCRM中disabled和Disabled屬性的區別
    一些常用的sql
    約會的客戶變更時取其它表的資料
    MSCRM儲存disabled欄位的值
    CRM显示产品图片
    顯示Object的所有屬性及處理ContactId只列出ParentCustomer的資料的javascript
    浅谈递归过程以及递归的优化
  • 原文地址:https://www.cnblogs.com/mj-liylho/p/8885430.html
Copyright © 2011-2022 走看看