delete pics to save space

p.CH1812.cpp

@@ -0,0 +1,94 @@
+//http://contest-hunter.org:83/contest/0x18%E3%80%8C%E5%9F%BA%E6%9C%AC%E6%95%B0%E6%8D%AE%E7%BB%93%E6%9E%84%E3%80%8D%E7%BB%83%E4%B9%A0/1812%20%E7%94%9F%E6%97%A5%E7%A4%BC%E7%89%A9
+#include<cstdio>
+#include<cstring>
+#include<queue>
+#include<algorithm>
+using namespace std;
+const int maxn=100005;
+int n,m,a[maxn];
+void Init()
+{
+	int tot=1,i=0; static int b[maxn];
+	while(i<n&&a[i]<0) i++;
+	if(i==n) { tot=0; return; }
+	b[0]=a[i]; i++;
+	for(;i<n;i++)
+	{
+		if((long long)a[i]*b[tot-1]>0) b[tot-1]+=a[i];
+		else b[tot++]=a[i];
+	}
+	n=tot;
+	for(int i=0;i<n;i++) a[i]=b[i];
+	if(a[n-1]<0) n--;
+}
+struct Node
+{
+	int val; bool alive;
+	Node *pre,*nxt; 
+};
+struct Data
+{
+	int val; Node *p;
+};
+priority_queue<Data> Q;
+inline bool operator<(const Data &a,const Data &b) { return a.val>b.val; }
+Node mem[maxn],*mcnt=mem,*head,*tail,*p;
+inline Node* InsertAfter(Node *p,int val)
+{
+	mcnt->val=val; mcnt->alive=true;
+	mcnt->pre=p; mcnt->nxt=p->nxt;
+	mcnt->nxt->pre=mcnt; mcnt->pre->nxt=mcnt;
+	Q.push((Data){abs(val),mcnt});
+//	printf("insert %d\n",abs(val));
+	return mcnt++;
+}
+inline void Erase(Node *p)
+{
+	p->alive=false;
+	p->pre->nxt=p->nxt;
+	p->nxt->pre=p->pre;
+}
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+	freopen("pro.out","w",stdout);
+#endif
+	scanf("%d%d",&n,&m);
+	for(int i=0;i<n;i++)
+	{
+		scanf("%d",&a[i]);
+		if(a[i]==0) { n--; i--; }
+	}
+	Init();
+	if(n==0||m==0) { puts("0"); return 0; }
+	head=mcnt++; tail=mcnt++; head->nxt=tail; tail->pre=head; p=head;
+	for(int i=0;i<n;i++) 
+	{
+		p=InsertAfter(p,a[i]);
+//		printf("%d : %d\n",i+1,a[i]);
+	}
+	p=head->nxt;
+	while(n/2+1>m)
+	{
+//		printf("n=%d\n",n);
+		Data u;
+		while(u=Q.top(),Q.pop(),!u.p->alive);
+	//	printf("choose %d\n",u.p->val);
+		if(u.p==head->nxt) { Erase(u.p->nxt); Erase(u.p); }
+		else if(u.p==tail->pre) { Erase(u.p->pre); Erase(u.p); }
+		else
+		{
+			u.p->val += u.p->pre->val + u.p->nxt->val;
+			Erase(u.p->pre); Erase(u.p->nxt);
+			Q.push((Data){abs(u.p->val),u.p});
+	//		printf("have %d new!\n",u.p->val);
+		}
+		n-=2;
+	}
+	int res=0;
+	p=head->nxt;
+	while(p!=tail) { res+=p->val>0?p->val:0; p=p->nxt; }
+	printf("%d\n",res);
+	return 0;
+}