#include <bits/stdc++.h>
using namespace std;
#define X first
#define Y second
#define mp make_pair
typedef long long ll;
typedef pair<int, int> ii;
struct line{
double a, b;
int cnt;
line(double _a = 0, double _b = 0, int _cnt = 0){
a = _a;
b = _b;
cnt = _cnt;
}
};
struct convexHull{
vector <line> d;
int ptr;
void reset(){
d.clear();
ptr = 0;
}
double calcY(const line &l, ll x){
return l.a * x + l.b;
}
bool bad(const line &l1, const line &l2, const line &l3){
return (l2.a - l3.a) * (l2.b - l1.b) >= (l1.a - l2.a) * (l3.b - l2.b);
}
void add(const line &newLine){
while (d.size() > 1){
if (bad(d[d.size() - 2], d[d.size() - 1], newLine))
d.pop_back();
else
break;
}
d.push_back(newLine);
}
double getMax(double x){
assert(!d.empty());
ptr = min(ptr, (int) d.size() - 1);
while (ptr < (int) d.size() - 1)
if (calcY(d[ptr], x) <= calcY(d[ptr + 1], x))
ptr++;
else
break;
return calcY(d[ptr], x);
}
int getCnt(double x){
assert(!d.empty());
ptr = min(ptr, (int) d.size() - 1);
while (ptr < (int) d.size() - 1)
if (calcY(d[ptr], x) <= calcY(d[ptr + 1], x))
ptr++;
else
break;
return d[ptr].cnt;
}
} cvh;
int n, k;
void readInput(){
cin >> n >> k;
}
int calcCnt(double cost){
cvh.reset();
double val = 0;
int cnt = 0;
for(int i = 1; i <= n; i++){
cvh.add(line(val, -(i - 1), cnt));
val = cvh.getMax(i) / i + 1 - cost;
cnt = cvh.getCnt(i) + 1;
}
return cnt;
}
double calcVal(double cost){
cvh.reset();
double val = 0;
int cnt = 0;
for(int i = 1; i <= n; i++){
cvh.add(line(val, -(i - 1), cnt));
val = cvh.getMax(i) / i + 1 - cost;
cnt = cvh.getCnt(i) + 1;
}
return val;
}
void solve(){
double l = 0, r = 1, best = -1;
for(int t = 1; t <= 200; t++){
double mid = (l + r) / 2.0;
if (calcCnt(mid) <= k){
best = mid;
r = mid;
} else {
l = mid;
}
}
calcCnt(best);
cout << fixed << setprecision(20) << calcVal(best) + best * k;
}
int main(){
readInput();
solve();
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
256 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
384 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
256 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
256 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
256 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
256 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
256 KB |
Output is correct |
2 |
Correct |
1 ms |
256 KB |
Output is correct |
3 |
Correct |
1 ms |
256 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
12 ms |
524 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
12 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
14 ms |
512 KB |
Output is correct |
3 |
Correct |
14 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
12 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
12 ms |
512 KB |
Output is correct |
2 |
Correct |
13 ms |
512 KB |
Output is correct |
3 |
Correct |
13 ms |
512 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
374 ms |
3572 KB |
Output is correct |
2 |
Correct |
393 ms |
3572 KB |
Output is correct |
3 |
Correct |
416 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
379 ms |
3572 KB |
Output is correct |
2 |
Correct |
442 ms |
3572 KB |
Output is correct |
3 |
Correct |
429 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
373 ms |
3572 KB |
Output is correct |
2 |
Correct |
420 ms |
3572 KB |
Output is correct |
3 |
Correct |
449 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
395 ms |
3572 KB |
Output is correct |
2 |
Correct |
413 ms |
3572 KB |
Output is correct |
3 |
Correct |
432 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
372 ms |
3572 KB |
Output is correct |
2 |
Correct |
415 ms |
3572 KB |
Output is correct |
3 |
Correct |
420 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
403 ms |
3572 KB |
Output is correct |
2 |
Correct |
396 ms |
3572 KB |
Output is correct |
3 |
Correct |
420 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
390 ms |
3572 KB |
Output is correct |
2 |
Correct |
383 ms |
3572 KB |
Output is correct |
3 |
Correct |
414 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
377 ms |
3572 KB |
Output is correct |
2 |
Correct |
426 ms |
3572 KB |
Output is correct |
3 |
Correct |
418 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
397 ms |
3572 KB |
Output is correct |
2 |
Correct |
399 ms |
3572 KB |
Output is correct |
3 |
Correct |
463 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
396 ms |
3572 KB |
Output is correct |
2 |
Correct |
400 ms |
3476 KB |
Output is correct |
3 |
Correct |
440 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
397 ms |
3572 KB |
Output is correct |
2 |
Correct |
431 ms |
3572 KB |
Output is correct |
3 |
Correct |
452 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
399 ms |
3572 KB |
Output is correct |
2 |
Correct |
416 ms |
3572 KB |
Output is correct |
3 |
Correct |
445 ms |
3572 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
414 ms |
3572 KB |
Output is correct |
2 |
Correct |
420 ms |
3572 KB |
Output is correct |
3 |
Correct |
450 ms |
3572 KB |
Output is correct |