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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 |
---|---|---|---|---|---|---|---|---|---|
#243414 | #6728. To the Park | Cipherxzc | AC ✓ | 39ms | 7740kb | C++20 | 2.2kb | 2023-11-08 10:19:26 | 2023-11-08 10:19:26 |
Judging History
answer
#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
#define LL long long
#define mp make_pair
const int N = 1e5 + 5;
int T, n;
bool notp[N], used[N];
vector<int> p, num[N];
void Euler(int lim){
for (int i = 2; i <= lim; i++){
if (!notp[i]){
p.push_back(i);
num[p.size() - 1].push_back(i);
}
for (int j = 0; j < p.size() && p[j] <= lim / i; j++){
notp[i * p[j]] = true;
num[j].push_back(i * p[j]);
if (i % p[j] == 0){
break;
}
}
}
}
int main(){
ios::sync_with_stdio(false);
cin.tie(0), cout.tie(0);
Euler(1e5);
// for (int i = 0; i < p.size(); i++){
// for (int j: num[i]){
// cout << j << ' ';
// }
// cout << endl;
// }
cin >> T;
while (T--){
cin >> n;
for (int i = 2; i <= n; i += 2){
used[i] = false;
}
vector<pair<int, int>> ans;
vector<int> vec;
for (int i = 1; i < p.size() && p[i] * 2 <= n; i++){
vec.clear();
for (int j = 0; j < num[i].size() && num[i][j] <= n; j++){
vec.push_back(num[i][j]);
}
int j = 0;
if (vec.size() & 1){
ans.push_back(mp(vec[0], vec[0] << 1));
used[vec[0] << 1] = true;
j = 1;
}
for (; j < vec.size(); j += 2){
ans.push_back(mp(vec[j], vec[j + 1]));
}
}
vec.clear();
for (int x: num[0]){
if (x > n){
break;
}
if (!used[x]){
vec.push_back(x);
}
}
for (int i = 0; i + 1 < vec.size(); i += 2){
ans.push_back(mp(vec[i], vec[i + 1]));
}
if (ans.size() == 0){
cout << ans.size() << endl;
}else{
cout << ans.size() << ' ';
for (int i = 0; i < ans.size(); i++){
cout << ans[i].first << ' ' << ans[i].second << " \n"[i == ans.size() - 1];
}
}
}
return 0;
}
这程序好像有点Bug,我给组数据试试?
详细
Test #1:
score: 100
Accepted
time: 2ms
memory: 6808kb
input:
3 1 4 6
output:
0 1 2 4 2 3 6 2 4
result:
ok 4 cases
Test #2:
score: 0
Accepted
time: 39ms
memory: 7740kb
input:
1007 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101...
output:
0 0 0 1 2 4 1 2 4 2 3 6 2 4 2 3 6 2 4 2 3 6 2 4 3 3 9 2 4 6 8 4 3 9 5 10 2 4 6 8 4 3 9 5 10 2 4 6 8 4 3 9 5 10 2 4 6 8 4 3 9 5 10 2 4 6 8 5 3 9 5 10 7 14 2 4 6 8 6 3 6 9 15 5 10 7 14 2 4 8 12 6 3 6 9 15 5 10 7 14 2 4 8 12 6 3 6 9 15 5 10 7 14 2 4 8 12 7 3 6 9 15 5 10 7 14 2 4 8 12 16 18 7 3 6 9 15 5...
result:
ok 1008 cases