Sereja and Swaps（贪心+暴力枚举区间）
AC_Code:
1 //枚举区间,o(n^2),然后将区间内最小的数逐个和区间外面最大的数交换 2 #include <bits/stdc++.h> 3 using namespace std; 4 typedef long long ll; 5 const int maxn = 205; 6 const int inf=0x3f3f3f3f; 7 #define rep(i,first,last) for(int i=first;i<=last;i++) 8 #define dep(i,first,last) for(int i=first;i>=last;i--) 9 int n,k,a[maxn],b[maxn]; 10 11 int solve(int l,int r){ 12 memcpy(b,a,sizeof(a)); 13 int ans=0; 14 rep(i,l,r) ans+=a[i]; 15 int p,q; 16 rep(i,1,k){ 17 int bMax=-inf,bMin=inf; 18 rep(j,1,n){ 19 if((j<l||j>r)&&b[j]>bMax ){ 20 bMax=b[j]; 21 p=j; 22 } 23 else if( j>=l && j<=r && b[j]<bMin ){ 24 bMin=b[j]; 25 q=j; 26 } 27 } 28 int t=bMax-bMin; 29 if( t<=0 ) break; 30 ans+=t; 31 swap(b[p],b[q]); 32 } 33 return ans; 34 } 35 int main() 36 { 37 scanf("%d%d",&n,&k); 38 int ans=-inf; 39 rep(i,1,n) scanf("%d",&a[i]); 40 rep(i,1,n){ 41 rep(j,i,n){ 42 ans=max(ans,solve(i,j)); 43 } 44 } 45 printf("%d\n",ans); 46 return 0; 47 }
