Codeforces Round #243 (Div. 2) C. Sereja and Swaps

#include<stdio.h>#include<algorithm>using namespace std;int main(){  freopen("in2.txt","r",stdin);  int n,k,a[500],b[500],c[500];  scanf("%d%d",&n,&k);  for(int i=1;i<=n;i++)  {    scanf("%d",&a[i]);  }  int i,j,p,q,ans=-200010;  for(int l=1;l<=n;l++)  {    for(int r=l;r<=n;r++)    {      for(p=1,i=l;i<=r;i++)b[p++]=a[i];      for(q=1,j=1;j<l;j++)c[q++]=a[j];      for(j=r+1;j<=n;j++)c[q++]=a[j];      sort(b+1,b+p);      sort(c+1,c+q);      //for(int i=1;i<p;i++)printf("%d ",b[i]);printf("\n");      //for(int i=1;i<q;i++)printf("%d ",c[i]);printf("\n");      for(int i=1,j=q-1;i<=k&&i<p&&j>=1;i++,j--)      {        if(c[j]>b[i])swap(b[i],c[j]);        else break;      }      int s=0;      for(int i=1;i<p;i++)      {        s+=b[i];      }      //printf("s=%d\n",s);      ans=max(ans,s);    }  }  printf("%d\n",ans);  return 0;}

A. Sereja and Swaps

time limit per test

1 second

memory limit per test

256 megabytes

input

standard input

output

standard output

As usual, Sereja has array a, its elements are integers: a[1], a[2], ..., a[n]. Let's introduce notation:

A swap operation is the following sequence of actions:

• choose two indexes i, j (i ≠ j);
• perform assignments tmp = a[i], a[i] = a[j], a[j] = tmp.

What maximum value of function m(a) can Sereja get if he is allowed to perform at most k swap operations?

Input

The first line contains two integers n and k (1 ≤ n ≤ 200; 1 ≤ k ≤ 10). The next line contains n integers a[1],a[2], ..., a[n] ( - 1000 ≤ a[i] ≤ 1000).

Output

In a single line print the maximum value of m(a) that Sereja can get if he is allowed to perform at most k swap operations.

Sample test(s)

input

10 210 -1 2 2 2 2 2 2 -1 10

output

32

input

5 10-1 -1 -1 -1 -1

output

-1

用了扬神的方法，暴力枚举区间，排序交换k次