#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x, y) ((x + y - 1) / (y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl
#define rep(i, n) for(int i = 0; i < n; ++i)
#define rep1(i, n) for(int i = 1; i <= n; ++i)
#define rev(i, s, e) for(int i = s; i >= e; --i)
#define trav(i, a) for(auto &i : a)
template<typename T>
void amin(T &a, T b) {
a = min(a, b);
}
template<typename T>
void amax(T &a, T b) {
a = max(a, b);
}
#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif
/*
refs:
edi
https://codeforces.com/blog/entry/53595?#comment-376650
f(i+1) > f(i)^2
#of non-lollipops = O(sqrt(n))
just check all non-lollipops for diamond
efficiently find all non-lollipops
*/
const int MOD = 1e9 + 7;
const int N = 2e5 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;
const int B = 455;
#include "prize.h"
vector<pii> dp(N,{-1,-1});
pii ask2(int i){
if(dp[i].ff != -1) return dp[i];
vector<int> v = ask(i);
return dp[i] = {v[0],v[1]};
}
int find_best(int n) {
int mx = -1, pos = -1;
rep(i,500){
auto [cl,cr] = ask2(i);
int cnt = cl+cr;
if(cnt == 0){
return i;
}
if(cnt > mx){
mx = cnt;
pos = i;
}
}
assert(pos != -1);
deque<int> dq;
for(int i = pos+B; i < n; ++i){
dq.pb(i);
}
trav(i,dq){
ask2(i);
}
// find the closest non-lollipop with ind > i
// given that the curr pos is a lollipop
while(pos < n-1){
while(!dq.empty() and dq.front() <= pos){
dq.pop_front();
}
auto [fcl,fcr] = ask2(pos);
int l = pos+1, r = n-1;
if(!dq.empty()){
l = dq.back()+1;
rep(i,sz(dq)){
auto [cl,cr] = ask2(dq[i]);
int cnt = cl+cr;
bool ok = false;
// mid is not a lollipop
if(cnt != mx){
ok = true;
}
else{
// mid is a lollipop
if(cl > fcl){
ok = true;
}
}
if(ok){
if(!i){
l = pos+1;
}
else{
l = dq[i-1]+1;
}
r = dq[i];
break;
}
}
}
int first = -1;
while(l <= r){
// is there a lollipop in range [pos,mid]?
int mid = (l+r) >> 1;
auto [cl,cr] = ask2(mid);
int cnt = cl+cr;
bool ok = false;
// mid is not a lollipop
if(cnt != mx){
ok = true;
}
else{
// mid is a lollipop
if(cl > fcl){
ok = true;
}
}
if(ok){
first = mid;
r = mid-1;
}
else{
l = mid+1;
}
}
if(first == -1){
break;
}
pos = -1;
// find the closest pos >= first that is a lollipop
for(int i = first; i < n; ++i){
auto [cl,cr] = ask2(i);
int cnt = cl+cr;
if(cnt == 0){
return i;
}
if(cnt == mx){
pos = i;
break;
}
}
if(pos == -1) break;
}
// assert(0);
return -1;
}
Compilation message
prize.cpp: In function 'int find_best(int)':
prize.cpp:28:36: warning: comparison of integer expressions of different signedness: 'int' and 'std::deque<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
28 | #define rep(i, n) for(int i = 0; i < n; ++i)
| ^
prize.cpp:118:4: note: in expansion of macro 'rep'
118 | rep(i,sz(dq)){
| ^~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
49 ms |
2784 KB |
Incorrect |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
43 ms |
2780 KB |
Incorrect |
| 2 |
Halted |
0 ms |
0 KB |
- |
