#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <ll, ll> pll;
vector <pll> L, R;
ll X[101010];
ll n, k, t;
bool check(ll v)
{
ll i, a, b, s;
L.clear(); R.clear();
for(i=1; i<k; i++){
a = X[i + 1] - X[i]; b = 2 * t * v - a;
for(; !L.empty() && b <= 0; L.pop_back()){
a = max(a, L.back().first);
b += L.back().second;
}
L.emplace_back(a, b);
}
for(i=n; i>k; i--){
a = X[i] - X[i - 1]; b = 2 * t * v - a;
for(; !R.empty() && b <= 0; R.pop_back()){
a = max(a, R.back().first);
b += R.back().second;
}
R.emplace_back(a, b);
}
s = 2 * t * v;
for(; ; ){
if(!L.empty() && s >= L.back().first && L.back().second > 0){
s += L.back().second; L.pop_back();
}
else if(!R.empty() && s >= R.back().first && R.back().second > 0){
s += R.back().second; R.pop_back();
}
else break;
}
if(L.size() > 1 || R.size() > 1) return 0;
else if(L.empty() && R.empty()) return 1;
else if(L.empty()) return s >= R[0].first;
else if(R.empty()) return s >= L[0].first;
else return (s >= L[0].first && s + L[0].second >= R[0].first)
|| (s >= R[0].first && s + R[0].second >= L[0].first);
}
int main()
{
ios::sync_with_stdio(false);
cin.tie(NULL);
ll i, s, e;
cin >> n >> k >> t;
for(i=1; i<=n; i++){
cin >> X[i];
}
for(s=0, e=1e12/t; s<=e; ){
if(check(s + e >> 1)) e = (s + e >> 1) - 1;
else s = (s + e >> 1) + 1;
}
cout << e + 1 << "\n";
return 0;
}
Compilation message
sparklers.cpp: In function 'int main()':
sparklers.cpp:70:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
if(check(s + e >> 1)) e = (s + e >> 1) - 1;
~~^~~
sparklers.cpp:70:32: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
if(check(s + e >> 1)) e = (s + e >> 1) - 1;
~~^~~
sparklers.cpp:71:15: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
else s = (s + e >> 1) + 1;
~~^~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
2 ms |
376 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |