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ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#478259 | #142. 平面最近点对 | Williamxzh# | 0 | 5ms | 6588kb | C++23 | 1.6kb | 2024-07-14 19:43:54 | 2024-07-14 19:43:54 |
answer
#include <bits/stdc++.h>
#define il inline
#define pii pair<int,int>
#define fi first
#define se second
using namespace std;
typedef long long ll;
const int N=2e6+5,inf=2e9;const ll oo=4e18;
int n,B,cnt;pii a[N];ll ans;
il ll dis(pii x,pii y){return 1ll*(x.fi-y.fi)*(x.fi-y.fi)+1ll*(x.se-y.se)*(x.se-y.se);}
int dx[9]={0,0,1,1,1,0,-1,-1,-1};
int dy[9]={0,1,1,0,-1,-1,-1,0,1};
unordered_map<ll,int> mp;
vector<pii> e[N];
il ll id(int x,int y){return 1ll*inf*(x/B)+1ll*(y/B);}
il void add(int i){
ll w=id(a[i].fi,a[i].se);
if(!mp.count(w)) mp[w]=++cnt;
e[mp[w]].push_back({a[i].fi,a[i].se});
}
int x,y,z,u,v,w;ll mi;ll p,q,r;
int main(){
//freopen("P1429_1.in","r",stdin);
mt19937 rnd(time(0));
scanf("%d",&n);
for(int i=1;i<=n;++i) scanf("%d%d",&a[i].fi,&a[i].se);
shuffle(a+1,a+1+n,rnd);
ans=dis(a[1],a[2]),B=sqrtl(ans)+1,add(1),add(2);
for(int i=3;i<=n;++i){
mi=oo,u=a[i].fi/B,v=a[i].se/B;
for(int j=0;j<9;++j){
if(u+dx[j]<0 || v+dy[j]<0) continue;
w=mp[1ll*(u+dx[j])*inf+(v+dy[j])];if(!w) continue;
for(pii it:e[w]) mi=min(mi,dis(a[i],it));
}
if(mi>=ans){add(i);continue;}
for(int j=1;j<=cnt;++j) e[j].clear();mp.clear();cnt=0;
ans=mi,B=sqrtl(ans)+1;
for(int j=1;j<=i;++j){
p=1ll*(a[j].fi/B)*inf+(a[j].se/B),u=mp[p];if(!u) mp[p]=++cnt,u=cnt;
e[u].push_back({a[j].fi,a[j].se});
}
//if(clock()>1900000){double dd=sqrtl(ans);printf("%.15lf",dd);exit(0);}
}
double dd=sqrtl(ans);
printf("%.15lf",dd);
return 0;
}
詳細信息
Subtask #1:
score: 0
Wrong Answer
Test #1:
score: 0
Wrong Answer
time: 5ms
memory: 6588kb
input:
2933 19320 28055 2053 27470 14635 1378 27582 9822 28729 107 22351 3093 17670 379 23901 4686 27182 12261 19443 8467 24208 20283 10763 10584 25953 28380 28290 27394 19572 14769 4024 12401 23295 3267 26949 176 13416 4517 23856 15413 26260 18957 18275 24409 999 3873 28202 14686 25446 2822 24009 8949 114...
output:
6.403124237432849
result:
wrong answer 1st numbers differ - expected: '2.8284271', found: '6.4031242', error = '1.2638463'
Subtask #2:
score: 0
Skipped
Dependency #1:
0%
Subtask #3:
score: 0
Skipped
Dependency #1:
0%
Subtask #4:
score: 0
Skipped
Dependency #1:
0%
Subtask #5:
score: 0
Skipped
Dependency #1:
0%