delete pics to save space

7.3709.cpp

@@ -0,0 +1,42 @@
+#include<cstdio>
+#include<cstring>
+#include<algorithm>
+using namespace std;
+typedef long long LL;
+const int maxn=500005;
+int T,n,m,Q[maxn],L,R;
+LL a[maxn],s[maxn],f[maxn],X[maxn],Y[maxn];
+int main()
+{
+	#ifdef local
+	freopen("pro.in","r",stdin);
+	#endif
+	scanf("%d",&T);
+	while(T-->0)
+	{
+		scanf("%d%d",&n,&m);
+		for(int i=1;i<=n;i++) scanf("%lld",&a[i]);
+		for(int i=1;i<=n;i++) s[i]=s[i-1]+a[i];
+		Q[L=R=1]=0;
+		X[0]=1;
+		for(int i=m;i<=2*m-1&&i<=n;i++)
+		{
+			f[i]=s[i]-i*a[1];
+			X[i]=a[i+1];
+			Y[i]=f[i]-s[i]+i*a[i+1];
+		}
+		for(int i=2*m;i<=n;i++)
+		{
+			int p=i-m;
+			while(L<R&&(Y[Q[R]]-Y[Q[R-1]])*(X[p]-X[Q[R-1]])>=(Y[p]-Y[Q[R-1]])*(X[Q[R]]-X[Q[R-1]])) R--;
+			Q[++R]=p;
+			while(L<R&&(Y[Q[L+1]]-Y[Q[L]])<=i*(X[Q[L+1]]-X[Q[L]])) L++;
+			int j=Q[L];
+			f[i]=f[j]+s[i]-s[j]-(i-j)*a[j+1];
+			X[i]=a[i+1];
+			Y[i]=f[i]-s[i]+i*a[i+1];
+		}
+		printf("%lld\n",f[n]);
+	}
+	return 0;
+}