这题很强势,写了半天炸了,判断山顶一直很懵逼,知道问了Claris才知道原来就是按照题目那样子暴力就好了= =。 找出所有山峰,然后贪心减去代价最小的= =
#include<cstdio> #include<algorithm> #include<cstring> #define fo(i,a,b) for(int i=a;i<=b;i++) #define fd(i,a,b) for(int i=a;i>=b;i--) using namespace std; const int N=1e3+5; int a[N],tmp; int n,m,i,j,k,x,y,t,l,r,ans; int main() { scanf("%d%d",&n,&m); for(a[0]=~0U>>1,i=1;i<=n;i++)scanf("%d",&a[i]),a[0]=a[0]<a[i]?a[0]:a[i]; for(a[n+1]=a[0],i=1;i<n;t++) { while (i<n&&a[i]<=a[i+1])i++; while (i<n&&a[i]>=a[i+1])i++; } for(m=t-m;m>0;m--) { for(i=0,tmp=~0U>>1;i<n;) { k=a[j=i]; while (i<=n&&a[i]<=a[i+1])i++; while (i<=n&&a[i]>=a[i+1])i++; if (a[i]>k)k=a[i]; for(t=0,x=j;x<=i;x++)if (a[x]>k)t+=a[x]-k; if (t<tmp)tmp=t,l=j,r=i,y=k; } for(ans+=tmp;l<=r;l++)if (a[l]>y)a[l]=y; } printf("%d\n",ans); }