zoukankan      html  css  js  c++  java
  • ACM-ICPC 2016 Qingdao Preliminary Contest G. Sort

    Recently, Bob has just learnt a naive sorting algorithm: merge sort. Now, Bob receives a task from Alice.
    Alice will give Bob N sorted sequences, and the i-th sequence includes ai elements. Bob need to merge all of these sequences. He can write a program, which can merge no more than k sequences in one time. The cost of a merging operation is the sum of the length of these sequences. Unfortunately, Alice allows this program to use no more than T cost. So Bob wants to know the smallest k to make the program complete in time.

     


    Input
    The first line of input contains an integer t0, the number of test cases. t0 test cases follow.
    For each test case, the first line consists two integers N (2N100000) and T (Ni=1ai<T<231).
    In the next line there are N integers a1,a2,a3,...,aN(i,0ai1000).
     


    Output
    For each test cases, output the smallest k.
     


    Sample Input
    1 5 25 1 2 3 4 5
     


    Sample Output
    3
     
     
     1 #include <iostream>
     2 #include <cstdio>
     3 #include <algorithm>
     4 #include <cstdlib>
     5 #include <cstring>
     6 #include <string>
     7 #include <deque>
     8 #include <queue>
     9 using namespace std;
    10 #define  ll long long 
    11 #define  N 100009
    12 #define  gep(i,a,b)  for(int  i=a;i<=b;i++)
    13 #define  gepp(i,a,b) for(int  i=a;i>=b;i--)
    14 #define  gep1(i,a,b)  for(ll i=a;i<=b;i++)
    15 #define  gepp1(i,a,b) for(ll i=a;i>=b;i--)    
    16 #define  mem(a,b)  memset(a,b,sizeof(a))
    17 int n,m,t;
    18 int sum[N],a[N];
    19 priority_queue<int,vector<int>,greater<int> >que;
    20 bool check(int k){
    21     while(!que.empty())  que.pop();
    22     int x=(n-1)%(k-1);//共需要归并n-1个数,每次要归并k-1个数
    23     int add=0;
    24     if(x){//为了不影响单调性
    25         x++;//每一次都是减去X个,又加一个。
    26         add+=sum[x];
    27         que.push(add);//先去掉x个,后面正常
    28     }
    29     gep(i,x+1,n) que.push(a[i]);
    30     int y=(n-1)/(k-1);//分步骤
    31     gep(i,0,y-1){
    32         int tmp=k;
    33         int tt=0;
    34         while(tmp--){//每次k个
    35             int v=que.top();
    36             que.pop();
    37             tt+=v;
    38         }
    39         que.push(tt);//再压入
    40         add+=tt;
    41     }
    42     return add<=m;//不超过m才行
    43 }
    44 int  main()
    45 {
    46     scanf("%d",&t);
    47     while(t--){
    48         scanf("%d%d",&n,&m);
    49         mem(a,0);
    50         mem(sum,0);
    51         gep(i,1,n) {
    52             scanf("%d",&a[i]);
    53         }
    54         sort(a+1,a+1+n);//要先排序
    55         gep(i,1,n){
    56             sum[i]=sum[i-1]+a[i];
    57         }
    58         int l=2,r=n;//至少2个
    59         while(l<=r){//r可能取到
    60             int mid=(r+l)>>1;
    61             if(check(mid)) r=mid-1;//r=mid是错的,会死循环
    62             else l=mid+1;
    63         }
    64         printf("%d
    ",r+1);
    65     }
    66     return 0;
    67 }
  • 相关阅读:
    CSS3 背景
    CSS3 边框
    CSS3中的transform变形
    兼容IE与firefox火狐的回车事件(js与jquery)
    JS相关链接
    JS操作DOM元素属性和方法
    用js给html设置style
    JavaScript数学函数(一)
    [JS] 如何清空file input框 [整理]
    未在本地计算机上注册Microsoft.ACE.OLEDB.12.0提供程序(Oledb)
  • 原文地址:https://www.cnblogs.com/tingtin/p/9477560.html
Copyright © 2011-2022 走看看