// header file
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
// pragma
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
// macros
// #define endl "\n"
#define ll long long
#define mp make_pair
#define ins insert
#define lb lower_bound
#define pb push_back
#define ub upper_bound
#define lll __int128
#define fi first
#define se second
using namespace std;
using namespace __gnu_pbds;
typedef tree<int, null_type, less_equal<int>, rb_tree_tag, tree_order_statistics_node_update> ordered_multiset;
typedef tree<int, null_type, less<int>, rb_tree_tag,tree_order_statistics_node_update> ordered_set;
const int lim = 6e5 + 5;
struct fenwick {
int a[lim];
fenwick() {
memset(a, 0, sizeof(a));
}
void update(int idx, int val) {
// cerr << idx << endl;
assert(idx > 0);
while(idx < lim) {
a[idx] += val;
idx += idx&-idx;
}
}
void update(int l, int r, int val) {
if(l > r)
return;
update(l, val);
update(r + 1, -val);
}
int query(int idx) {
if(idx >= lim)
idx = lim - 1;
int res = 0;
while(idx) {
res += a[idx];
idx -= idx&-idx;
}
return res;
}
};
int main() {
ios_base::sync_with_stdio(0); cin.tie(NULL);
int n;
cin >> n;
int a[2 * n + 5];
for(int i = 1; i <= 2 * n; ++i)
cin >> a[i];
int b[n + 5], c[n + 5];
for(int i = 1; i <= n; ++i)
cin >> b[i];
for(int i = 1; i <= n; ++i)
cin >> c[i];
sort(b + 1, b + n + 1);
sort(c + 1, c + n + 1);
int l = 0, r = 1e9, res = -1;
vector<pair<int, int>> v;
for(int i = 1; i <= 2 * n; ++i)
v.pb(mp(a[i], i));
sort(v.begin(), v.end());
fenwick cur;
while(l <= r) {
memset(cur.a, 0, sizof(cur.a));
int mid = (l + r) >> 1;
// max diff -> mid
// try each partition what is the max diff
// nanti ada banyak validity test, tinggal cek validity testnya mana aja
pair<int, int> validb[2 * n + 5], validr[2 * n + 5];
for(int i = 1; i <= 2 * n; ++i) {
// idx of element >= a[i] - mid
validb[i].fi = lower_bound(b + 1, b + n + 1, a[i] - mid) - b;
// idx of element <= a[i] + mid
validb[i].se = upper_bound(b + 1, b + n + 1, a[i] + mid) - b - 1;
// idx of element >= a[i] - mid
validr[i].fi = lower_bound(c + 1, c + n + 1, a[i] - mid) - c;
// idx of element <= a[i] + mid
validr[i].se = upper_bound(c + 1, c + n + 1, a[i] + mid) - c - 1;
// if(mid == 1) {
// cerr << a[i] + mid << " " << upper_bound(c + 1, c + n + 1, a[i] + mid) - c - 1 << " " << validr[i].se << endl;
// }
}
set<int> blue, red;
for(int i = 1; i <= 2 * n; ++i)
blue.ins(i), red.ins(i);
for(auto p : v) {
// process
// cerr << "UPDATE" << endl;
cur.update(max(1, p.se - n + 1), p.se, 1);
// observe that blue on left/right of that segment can be invalid
auto it = blue.begin();
int idx = p.se;
// cerr << "TEST" << endl;
while(blue.size() && (it = blue.lb(p.se - n + 1)) != blue.end() && *it <= p.se) {
int tmp2 = cur.query(*it);
if(tmp2 < validb[idx].fi || tmp2 > validb[idx].se)
blue.erase(it);
else
break;
}
while(blue.size() && (it = blue.ub(p.se)) != blue.begin() && *--it >= p.se - n + 1) {
int tmp2 = cur.query(*it);
if(tmp2 < validb[idx].fi || tmp2 > validb[idx].se)
blue.erase(it);
else
break;
}
if(p.se <= n) {
cur.update(p.se + n + 1, 2 * n, 1);
// observe that blue on left/right of that segment can be invalid
while(blue.size() && (it = blue.lb(p.se + n + 1)) != blue.end() && *it <= p.se + 2 * n) {
int tmp2 = cur.query(*it);
if(tmp2 < validb[idx].fi || tmp2 > validb[idx].se)
blue.erase(it);
else
break;
}
while(blue.size() && (it = blue.ub(p.se + 2 * n)) != blue.begin() && *--it >= p.se + n + 1) {
int tmp2 = cur.query(*it);
if(tmp2 < validb[idx].fi || tmp2 > validb[idx].se)
blue.erase(it);
else
break;
}
}
// cerr << "TEST" << endl;
while(red.size() && (it = red.lb(p.se - n + 1)) != red.end() && *it <= p.se) {
// cerr << "check " << *it << " due to " << p.se << " " << cur.query(*it) << " " << validr[idx].fi << endl;
int tmp2 = cur.query(*it);
if(tmp2 < validr[idx].fi || tmp2 > validr[idx].se) {
// cerr << "delete1 " << *it << " due to " << p.se << endl;
red.erase(it);
}
else
break;
}
while(red.size() && (it = red.ub(p.se)) != red.begin() && *--it >= p.se - n + 1) {
// cerr << "check " << *it << " due to " << p.se << " " << cur.query(*it) << " " << validr[idx].se << endl;
int tmp2 = cur.query(*it);
if(tmp2 < validr[idx].fi || tmp2 > validr[idx].se) {
// cerr << "delete2 " << *it << " due to " << p.se << endl;
red.erase(it);
}
else
break;
}
if(p.se <= n) {
// observe that red on left/right of that segment can be invalid
while(red.size() && (it = red.lb(p.se + n + 1)) != red.end() && *it <= p.se + 2 * n) {
// cerr << "check " << *it << " due to " << p.se << " " << cur.query(*it) << " " << validr[idx].fi << endl;
int tmp2 = cur.query(*it);
if(tmp2 < validr[idx].fi || tmp2 > validr[idx].se) {
// cerr << "delete " << *it << " due to " << p.se << endl;
red.erase(it);
}
else
break;
}
while(red.size() && (it = red.ub(p.se + 2 * n)) != red.begin() && *--it >= p.se + n + 1) {
// cerr << "check " << *it << " due to " << p.se << " " << cur.query(*it) << " " << validr[idx].se << endl;
int tmp2 = cur.query(*it);
if(tmp2 < validr[idx].fi || tmp2 > validr[idx].se) {
// cerr << "delete " << *it << " due to " << p.se << endl;
red.erase(it);
}
else
break;
}
}
}
// blue and red have to complement each other
bool ans = 0;
for(auto x : blue) {
if(red.count(x - n) || red.count(x + n))
ans = 1;
}
/*
if(mid <= 20) {
cerr << "DEBUG " << mid << endl;
for(auto x : red) {
cerr << x << " ";
}
cerr << endl;
for(auto x : blue) {
cerr << x << " ";
}
cerr << endl;
}
*/
if(ans)
r = mid - 1, res = mid;
else
l = mid + 1;
}
cout << res << endl;
// choose a contiguous segment L to R such that we use one color
// N^2 approach -> pair greedily (sorted)
// int res = 1e9;
// for(int i = 1; i + n <= 2 * n + 1; ++i) {
// vector<int> blue, red;
// for(int j = 1; j < i; ++j) {
// blue.pb(a[j]);
// }
// for(int j = i; j < i + n; ++j) {
// red.pb(a[j]);
// }
// for(int j = i + n; j <= 2 * n; ++j) {
// blue.pb(a[j]);
// }
// sort(blue.begin(), blue.end());
// sort(red.begin(), red.end());
// int mx = 0;
// for(int k = 1; k <= n; ++k) {
// mx = max({mx, abs(blue[k - 1] - b[k]), abs(red[k - 1] - c[k])});
// }
// res = min(res, mx);
// mx = 0;
// swap(red, blue);
// for(int k = 1; k <= n; ++k) {
// mx = max({mx, abs(blue[k - 1] - b[k]), abs(red[k - 1] - c[k])});
// }
// res = min(res, mx);
// }
// cout << res << endl;
return 0;
}
Compilation message
Main.cpp: In function 'int main()':
Main.cpp:75:22: error: 'sizof' was not declared in this scope
75 | memset(cur.a, 0, sizof(cur.a));
| ^~~~~
