Submission #375777

#	Time	Username	Problem	Language	Result	Execution time	Memory
375777		daniel920712	Two Antennas (JOI19_antennas)	C++14	22 / 100	304 ms	82072 KiB

antennas

#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <vector>

using namespace std;
struct A
{

    int l,r;
    int nxl,nxr;
    pair < int , int > ans;
}Node[1000005];
int all[1000005],now=1;
int l[1000005],r[1000005];
int x[1000005],y[1000005];
vector < pair < int , int > > in[1000005];
vector < pair < int , int > > out[1000005];
pair < int , int > operator+(pair < int , int > a,pair < int , int > b)
{
    return make_pair(max(a.first,b.first),min(a.second,b.second));
}
void build(int l,int r,int here)
{
    Node[here].l=l;
    Node[here].r=r;
    if(l==r)
    {
        Node[here].ans=make_pair(0,2e9);
        return;
    }
    Node[here].nxl=now++;
    Node[here].nxr=now++;
    build(l,(l+r)/2,Node[here].nxl);
    build((l+r)/2+1,r,Node[here].nxr);
    Node[here].ans=Node[Node[here].nxl].ans+Node[Node[here].nxr].ans;
}
void cha(int where,pair < int , int > con,int here)
{
    if(where==Node[here].l&&where==Node[here].r)
    {
        Node[here].ans=con;
        return;
    }
    if(where<=(Node[here].l+Node[here].r)/2) cha(where,con,Node[here].nxl);
    else cha(where,con,Node[here].nxr);
    Node[here].ans=Node[Node[here].nxl].ans+Node[Node[here].nxr].ans;
}
pair < int , int > Find(int l,int r,int here)
{
    if(l==Node[here].l&&r==Node[here].r) return Node[here].ans;
    if(r<=(Node[here].l+Node[here].r)/2) return Find(l,r,Node[here].nxl);
    else if(l>(Node[here].l+Node[here].r)/2) return Find(l,r,Node[here].nxr);
    else return Find(l,(Node[here].l+Node[here].r)/2,Node[here].nxl)+Find((Node[here].l+Node[here].r)/2+1,r,Node[here].nxr);
}
pair < int , int > tt;
int main()
{
    int N,M,ok=0,ans=0,i;
    scanf("%d",&N);
    for(i=1;i<=N;i++)
    {
        scanf("%d %d %d",&all[i],&l[i],&r[i]);
        if(i-l[i]>=1)
        {
            in[max(1,i-r[i])].push_back(make_pair(i,all[i]));
            out[i-l[i]+1].push_back(make_pair(i,all[i]));
        }
    }
    scanf("%d",&M);
    for(i=1;i<=M;i++) scanf("%d %d",&x[i],&y[i]);
    build(1,N,0);
    for(i=1;i<=N;i++)
    {
        for(auto j:in[i])
        {
            //printf("aa %d %d\n",i,j);
            cha(j.first,make_pair(j.second,j.second),0);
        }
        for(auto j:out[i]) cha(j.first,make_pair(0,2e9),0);
        if(i+l[i]<=N)
        {
            tt=Find(i+l[i],min(N,i+r[i]),0);
            if(tt.first) ans=max(ans,abs(all[i]-tt.first));
            if(tt.second!=2000000000) ans=max(ans,abs(all[i]-tt.second));
        }


    }
    if(ans==0) printf("-1\n");
    else printf("%d\n",ans);

    return 0;
}

Compilation message (stderr)

antennas.cpp: In function 'int main()':
antennas.cpp:59:13: warning: unused variable 'ok' [-Wunused-variable]
   59 |     int N,M,ok=0,ans=0,i;
      |             ^~
antennas.cpp:60:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   60 |     scanf("%d",&N);
      |     ~~~~~^~~~~~~~~
antennas.cpp:63:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   63 |         scanf("%d %d %d",&all[i],&l[i],&r[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
antennas.cpp:70:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   70 |     scanf("%d",&M);
      |     ~~~~~^~~~~~~~~
antennas.cpp:71:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   71 |     for(i=1;i<=M;i++) scanf("%d %d",&x[i],&y[i]);
      |                       ~~~~~^~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 2
• Subtask 2: 0 / 11
• Subtask 3: 22 / 22
• Subtask 4: 0 / 65