Ballot evaluation

Ballot evaluation

Time Limit:1000MS  Memory Limit:65536K
Total Submit:26 Accepted:4

Description

Bruce Force has gone to Las Vegas, the El Dorado for gamblers. He is interested especially in one betting game, where a machine forms a sequence of n numbers by drawing random numbers. Each player should estimate beforehand, how many increasing subsequences of length k will exist in the sequence of numbers.
A subsequence of a sequence a1, ..., an is defined as ai1, ..., ail, where 1 ≤ i1 < i2 < ... < il ≤ n. The subsequence is increasing, if aij-1 < aij for all 1 < j ≤ l.
Bruce doesn't trust the Casino to count the number of increasing subsequences of length k correctly. He has asked you if you can solve this problem for him.

Input

The input contains several test cases. The first line of each test case contains two numbers n and k (1 ≤ k ≤ n ≤ 100), where n is the length of the sequence drawn by the machine, and k is the desired length of the increasing subsequences. The following line contains n pairwise distinct integers ai (-10000 ≤ ai ≤ 10000 ), where ai is the ith number in the sequence drawn by the machine.
The last test case is followed by a line containing two zeros.

Output

For each test case, print one line with the number of increasing subsequences of length k that the input sequence contains. You may assume that the inputs are chosen in such a way that this number fits into a 64 bit signed integer (in C/C++, you may use the data type "long long", in Java the data type "long").

Sample Input

10 5
1 2 3 4 5 6 7 8 9 10
3 2
3 2 1
0 0

 

Sample Output

252
0

 

Source

2008/2009 University of Ulm Local Contest

chg

1261

Accepted

388K

734MS

G++

1.5K

2010-05-09 00:19:09

//一看到此题就感觉map会比较简单，直接映射出值来。一遍就ac了。

//本题还要注意的一定是精度问题，由于double类型的精度3.2其实为3.19999999，这样的话会造成数据丢失

//处理办法为加上一个微小的增量，见代码。

#include<iostream>
#include<map>
#include<sstream>
using namespace std;

int main()
{
 int n,m,i,j,rateInt,k;
 string name,s,str;
 double rate;
 map<string,int> data;
 while(scanf("%d%d",&n,&m)!=EOF)
 {
  for(i=0;i<n;i++)
  {
   cin>>name>>rate;
   rateInt=(rate+0.0000001)*10;
   data.insert(pair<string,int>(name,rateInt));
  }
  k=0;
  getline(cin,s);
  for(j=0;j<m;j++)
  {
   k++;
   getline(cin,s);
   istringstream sin(s);
   int sum=0,temp;
   while(sin>>str)
   {
    if(str=="+")
     continue;
    else if(str!="<"&&str!=">="&&str!="<="&&str!=">"&&str!="=")
    {
     temp=data[str];
     sum+=temp;
    }
    else if(str=="<"||str==">="||str=="<="||str==">"||str=="=")
     break;
   }
   sin>>temp;
   if(str==">")
   {
    if(sum>temp*10)
     printf("Guess #%d was correct./n",k);
    else
     printf("Guess #%d was incorrect./n",k);
   }
   else if(str==">=")
   {
    if(sum>=temp*10)
     printf("Guess #%d was correct./n",k);
    else
     printf("Guess #%d was incorrect./n",k);
   }
   else if(str=="<")
   {
    if(sum<temp*10)
     printf("Guess #%d was correct./n",k);
    else
     printf("Guess #%d was incorrect./n",k);
   }
   else if(str=="<=")
   {
    if(sum<=temp*10)
     printf("Guess #%d was correct./n",k);
    else
     printf("Guess #%d was incorrect./n",k);
   }
   else if(str=="=")
   {
    if(sum==temp*10)
     printf("Guess #%d was correct./n",k);
    else
     printf("Guess #%d was incorrect./n",k);
   }
  }
 }
}