1 #include<bits/stdc++.h>
 2 #define int long long
 3 using namespace std;
 4 const int N=1e5+11;
 5 int n,h[N],a[N],ans[N];
 6 int sta[N],top;
 7  
 8 inline int re_ad() {
 9     char ch=getchar(); int x=0,f=1;
10     while(ch<'0' || ch>'9') { if(ch=='-') f=-1; ch=getchar(); }
11     while
 
('0'<=ch && ch<='9') x=(x<<1)+(x<<3)+ch-'0',ch=getchar();
12     return x*f;
13 }
14  
15 signed main()
16 {
17     n=re_ad();
18     for(int i=1;i<=n;++i) h[i]=re_ad(),a[i]=re_ad();
19     top=0; memset(sta,0,sizeof(sta));
20     for(int i=1;i<=n;++i) {
21         while(h[sta[top]]<=h[i] && top) --top;
 
22         ans[sta[top]]+=a[i];
23         sta[++top]=i;
24     }
25     top=0; memset(sta,0,sizeof(sta));
26     for(int i=n;i>=1;--i) {
27         while(h[sta[top]]<=h[i] && top) --top;
28         ans[sta[top]]+=a[i];
29         sta[++top]=i;
30     }
31     int maxx=0;
32     for(int i=1
 
;i<=n;++i) maxx=max(maxx,ans[i]);
33     printf("%lld\n",maxx);
34 //  system("pause");
35     return 0;
36 }

 1 #include<bits/stdc++.h>
 2 using namespace std;
 3 const int N=1e4+11,Tree_Sz=5e4+11;
 4 int n,m,c;
 5  
 6 struct Point {
 7     int x,y;
 8     bool operator < (const Point &B) const {
 9         return (x==B.x)?y<B.y:x<B.x;
10     }
11 }a[N];
12  
13 inline int re_ad() {
14     char ch=getchar(); int x=0,f=1;
15     while(ch<'0' || ch>'9') { if(ch=='-') f=-1; ch=getchar(); }
16     while('0'<=ch && ch<='9') x=(x<<1)+(x<<3)+ch-'0',ch=getchar();
17     return x*f;
18 }
19  
20 struct SegmentTree {
21     struct Node {
22         int val,tag;
23     }t[Tree_Sz];
24     inline void Init() {
25         memset(t,0,sizeof(t));
26     }
27     inline void Pushup(int d) {
28         t[d].val=max(t[d<<1].val,t[d<<1|1].val);
29     }
30     inline void Pushdown(int d,int l,int r) {
31         t[d<<1].tag+=t[d].tag;
32         t[d<<1|1].tag+=t[d].tag;
33         t[d<<1].val+=t[d].tag;
34         t[d<<1|1].val+=t[d].tag;
35         t[d].tag=0;
36     }
37     void modify(int d,int l,int r,int x,int y,int z) {
38         if(x<=l && r<=y) { t[d].tag+=z,t[d].val+=z; return ; }
39         Pushdown(d,l,r);
40         int mid=(l+r)>>1;
41         if(x<=mid) modify(d<<1,l,mid,x,y,z);
42         if(y>=mid+1) modify(d<<1|1,mid+1,r,x,y,z);
43         Pushup(d);
44     }
45     inline void Modify(int x,int y,int z) {
46         modify(1,1,n,x,y,z);
47     }
48     inline int Query() {
49         return t[1].val;
50     }
51 }st;
52  
53 inline bool check(int d) {
54     st.Init();
55     for(int i=1,j=1,ed;i<=m;++i) {
56         ed=max(1,a[i].x-d+1);
57         st.Modify(max(1,a[i].y-d+1),a[i].y,1);
58         while(a[j].x<ed) st.Modify(max(1,a[j].y-d+1),a[j].y,-1),++j;
59         if(st.Query()>=c) return true;
60     }
61     return false;
62 }
63  
64 int main()
65 {
66     c=re_ad(),m=re_ad();
67     for(int i=1;i<=m;++i) a[i].x=re_ad(),a[i].y=re_ad(),n=max(n,max(a[i].x,a[i].y));
68     sort(a+1,a+m+1);
69     int l=1,r=n,ans=n+1;
70     while(l<=r) {
71         int mid=(l+r)>>1; //printf("mid: %d\n",mid);
72         if(check(mid)) r=mid-1,ans=mid;
73         else l=mid+1;
74     }
75     printf("%d\n",l);
76     return 0;
77 }

三分做法：

 1 #include<bits/stdc++.h>
 2 #define double long double
 3 using namespace std;
 4 const int N=1e5+11;
 5 const double St=1e12*1.0,eps=1e-8;
 6 int n;
 7  
 8 struct Node {
 9     double t,v;
10     bool operator < (const Node &B) const {
11         return t<B.t;
12     }
13 }a[N];
14  
15 double Calc(double d) {
16     double maxx=0.0,minn=St,tmp;
17     for(int i=1;i<=n;++i) {
18         tmp=a[i].v*(d-a[i].t);
19         maxx=max(maxx,tmp),minn=min(minn,tmp);
20     }
21     return maxx-minn;
22 }
23  
24 int main()
25 {
26     scanf("%d",&n);
27     for(int i=1;i<=n;++i) cin>>a[i].t>>a[i].v;
28     sort(a+1,a+n+1);
29     double l=a[n].t,r=St;
30     while(r-l>eps) {
31         double mid1=l+(r-l)/3,mid2=r-(r-l)/3;
32 //      printf("%.8Lf %.8Lf %.8Lf %.8Lf %.8Lf\n",l,r,mid1,mid2,r-l);
33         if(Calc(mid1)<Calc(mid2)) r=mid2;
34         else l=mid1;
35     }
36     printf("%.2Lf\n",Calc(l));
37 //  if(n==2) printf("%.8Lf %.8Lf %.8Lf %.8Lf\n",a[1].t,a[1].v,a[2].t,a[2].v);
38     return 0;
39 }