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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 |
---|---|---|---|---|---|---|---|---|---|
#798499 | #8790. First Billion | q1w2e3r4# | TL | 0ms | 0kb | C++14 | 2.6kb | 2024-12-04 14:12:38 | 2024-12-04 14:12:47 |
answer
#include<bits/stdc++.h>
using namespace std;
#define int long long
#include<random>
mt19937_64 rng(time(0));
int n;
int a[105];
vector<int> v[405];
const int SZ = 3000;
int findkth(int k, vector<int>& v, int l, int r){
if(r - l == 1){
int a = 1;
}
// cout << "kth " << l << " " << r << endl;
if(l == r) return v[l];
int len = r - l + 1;
int idx = l + rng() % len;
int pivot = v[idx];
vector<int> small, big;
for(int i=l;i<=r;i++){
int x = v[i];
if(x <= pivot) small.push_back(x);
else big.push_back(x);
}
int n = small.size(), m = big.size();
for(int i=0;i<n;i++){
v[i+l] = small[i];
}
for(int i=0;i<m;i++){
v[i+n+l] = big[i];
}
if(!n || !m) return pivot;
small.clear(), big.clear();
if(n >= k) return findkth(k, v, l, l+n-1);
else return findkth(k-n, v, l+n, r);
}
void build(int id, int l, int r){
if(l == r){
v[id].push_back(a[l]);
v[id].push_back(0);
return;
}
int mid = l + r >> 1;
build(id*2, l, mid);
build(id*2+1, mid+1, r);
vector<int> tmp;
for(int x: v[id*2]){
for(int y: v[id*2+1]){
tmp.push_back(x+y);
}
}
if(tmp.size() >= SZ){
int n = tmp.size();
int al = findkth(n/2 - SZ/2, tmp, 0, n-1), ar = findkth(n/2 + SZ/2 - 1, tmp, 0, n-1);
for(int x: tmp){
if(x >= al && x <= ar){
v[id].push_back(x);
}
}
}
else{
v[id] = tmp;
}
}
void query(int id, int l, int r, int target, vector<int>& ans){
// cout << "query " << l << " " << r << " " << target << endl;
if(l == r){
if(target == a[l]) ans.push_back(l);
assert(target == 0 || target == a[l]);
return;
}
int mid = l + r >> 1;
for(auto x: v[id*2]){
for(int y: v[id*2+1]){
if(x + y == target){
query(id*2, l, mid, x, ans);
query(id*2+1, mid+1, r, y, ans);
return;
}
}
}
}
signed main(){
// cin >> n;
// for(int i=1;i<=n;i++) cin >> a[i];
int n = 100;
for(int i=1;i<=n;i++){
a[i] = rng() % (int)4e7 + 1;
// cout << a[i] << " ";
}
cout << endl;
build(1,1,n);
bool ok = false;
for(auto x: v[1]){
// cout << x << " ";
if(x == 1e9) ok = true;
}
// assert(ok);
vector<int> ans;
query(1,1,n,(int)1e9,ans);
cout << ans.size();
for(int x: ans){
cout << " " << x;
}
}
详细
Test #1:
score: 0
Time Limit Exceeded
input:
10 386413329 88494216 245947398 316438989 192751270 204627269 65749456 3938400 150458676 345180997