#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include "temp.cpp"
#include <cstdio>
using namespace std;
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) x.clear()
#define uniq(x) x.resize(unique(all(x)) - x.begin());
#define blt __builtin_popcount
#define pb push_back
#define pf push_front
#define popf pop_front
#define popb pop_back
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(long double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
template <class T> void print(set <T> v);
template <class T> void print(vector <T> v);
template <class T> void print(multiset <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T, class V> void print(pair <T, V> p);
template <class T, class V> void print(T v[],V n) {cerr << "["; for(int i = 0; i < n; i++) {print(v[i]); cerr << " "; } cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque<T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(unordered_map<T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
// for grid problems
int dx[8] = {-1,0,1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
fastIO();
if (str != "" && str != "input") {
freopen((str + ".in").c_str(), "r", stdin);
freopen((str + ".out").c_str(), "w", stdout);
}
if(str == "input") {
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
}
}
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
int n;
void solve_() {
cin >> n;
set<int> st;
vector<int> a(n + 1), b(2 * n), used(2 * n);
for(int i = 1; i <= 2 * n - 1; i++) {
st.insert(i);
}
for(int i = 1; i <= n; i++) {
cin >> a[i];
auto it = st.find(a[i]);
if(it != st.end()) {
st.erase(it);
}
}
b[1] = a[1];
used[a[1]] = 1;
for(int i = 2; i <= n; i++) {
if(a[i] == a[i - 1]) {
// a[i] lower
// a[i] upper
b[2 * i - 1] = *st.begin();
b[2 * i - 2] = *prev(st.end());
used[b[2 * i - 2]] = true;
st.erase(st.begin());
st.erase(prev(st.end()));
}
if(a[i] > a[i - 1]) {
// a[i] upper
// a[i] upper
if (!used[a[i]]) {
b[2 * i - 1] = a[i];
used[b[2 * i - 1]] = true;
b[2 * i - 2] = *prev(st.end());
used[b[2 * i - 2]] = true;
st.erase(prev(st.end()));
} else {
b[2 * i - 1] = *prev(st.end());
used[b[2 * i - 1]] = true;
st.erase(prev(st.end()));
b[2 * i - 2] = *prev(st.end());
used[b[2 * i - 2]] = true;
st.erase(prev(st.end()));
}
}
if(a[i] < a[i - 1]) {
// a[i] lower
// a[i] lower
if (!used[a[i]]) {
b[2 * i - 1] = a[i];
used[b[2 * i - 1]] = true;
b[2 * i - 2] = *st.begin();
used[b[2 * i - 2]] = true;
st.erase(st.begin());
} else {
b[2 * i - 1] = *st.begin();
used[b[2 * i - 1]] = true;
st.erase(st.begin());
b[2 * i - 2] = *st.begin();
used[b[2 * i - 2]] = true;
st.erase(st.begin());
}
}
}
for(int i = 1; i <= 2 * n - 1; i++) {
printf("%d ", b[i]);
}
}
int main() {
setIO("");
auto solve = [&](int test_case)-> void {
while(test_case--) {
solve_();
}
};
int test_cases = 1;
solve(test_cases);
return 0;
}
Compilation message
medians.cpp: In function 'void setIO(std::string)':
medians.cpp:67:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
67 | freopen((str + ".in").c_str(), "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
medians.cpp:68:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
68 | freopen((str + ".out").c_str(), "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
medians.cpp:72:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
72 | freopen("input.txt", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
medians.cpp:73:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
73 | freopen("output.txt", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
212 KB |
Output is correct |
| 2 |
Correct |
0 ms |
212 KB |
Output is correct |
| 3 |
Correct |
1 ms |
212 KB |
Output is correct |
| 4 |
Correct |
0 ms |
212 KB |
Output is correct |
| 5 |
Correct |
0 ms |
212 KB |
Output is correct |
| 6 |
Correct |
0 ms |
212 KB |
Output is correct |
| 7 |
Correct |
0 ms |
212 KB |
Output is correct |
| 8 |
Correct |
0 ms |
212 KB |
Output is correct |
| 9 |
Correct |
1 ms |
212 KB |
Output is correct |
| 10 |
Correct |
1 ms |
212 KB |
Output is correct |
| 11 |
Correct |
1 ms |
340 KB |
Output is correct |
| 12 |
Correct |
1 ms |
340 KB |
Output is correct |
| 13 |
Correct |
1 ms |
340 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
2 ms |
468 KB |
Output is correct |
| 2 |
Correct |
4 ms |
724 KB |
Output is correct |
| 3 |
Correct |
6 ms |
1236 KB |
Output is correct |
| 4 |
Correct |
12 ms |
2260 KB |
Output is correct |
| 5 |
Correct |
25 ms |
4296 KB |
Output is correct |
| 6 |
Correct |
54 ms |
8264 KB |
Output is correct |
| 7 |
Correct |
87 ms |
12948 KB |
Output is correct |
