#include <bits/stdc++.h>
using namespace std;
typedef long long LL;
LL reach(vector<LL> a, vector<LL> b){
if(a[0] < b[0]) return 0;
vector<pair<LL,LL> > acompress, bcompress;
LL acur = a[0];
LL curmin = a[0];
for(LL i = 0; i < a.size(); i++){
if(a[i] >= acur){
acompress.push_back({acur, curmin});
acur = a[i];
curmin = a[i];
}
curmin = min(curmin, a[i]);
}
assert(acur == a[a.size()-1]);
LL bcur = b[0];
LL curmax = b[0];
for(LL i = 0; i < b.size(); i++){
if(b[i] <= bcur){
bcompress.push_back({bcur, curmax});
bcur = b[i];
curmax = b[i];
}
curmax = max(curmax, b[i]);
}
assert(bcur == b[b.size()-1]);
LL i = 0;
LL j = 0;
while(i < acompress.size() - 1 && j < bcompress.size() - 1){
if(bcompress[j+1].second <= acompress[i].first){
j++;
} else if(bcompress[j].first <= acompress[i+1].second){
i++;
} else {
return 0;
}
}
return 1;
}
LL ok(vector<LL> a, vector<LL> b){
LL dp[a.size()][b.size()];
for(int i = 0; i < a.size(); i++){
for(int j = 0; j < b.size(); j++){
dp[i][j] = 0;
if(a[i] >= b[j]){
if((i == 0 && j == 0) || (i > 0 && dp[i-1][j]) || (j > 0 && dp[i][j-1])){
dp[i][j] = 1;
}
}
}
}
return dp[a.size()-1][b.size()-1];
}
LL okay(vector<LL> a, vector<LL> b){
LL ma = 0;
LL mb = 0;
for(LL j = 0; j < a.size(); j++){
if(a[j] > a[ma]) ma = j;
}
for(LL j = 0; j < b.size(); j++){
if(b[j] < b[mb]) mb = j;
}
if(a[ma] < b[mb]) return 0;
vector<LL> la, lb;
vector<LL> ra, rb;
for(LL j = 0; j <= ma; j++) la.push_back(a[j]);
for(LL j = a.size()-1; j >= ma; j--) ra.push_back(a[j]);
for(LL j = 0; j <= mb; j++) lb.push_back(b[j]);
for(LL j = b.size()-1; j >= mb; j--) rb.push_back(b[j]);
return reach(la, lb) && reach(ra, rb);
}
int main(){
cin.sync_with_stdio(0); cin.tie(0);
LL n, k, t;
cin >> n >> k >> t;
k--;
vector<LL> x(n);
for(LL i = 0; i < n; i++){
cin >> x[i];
}
LL s = -1;
LL e = 1000000000;
while(s + 1 < e){
LL m = (s + e) / 2;
vector<LL> y = x;
for(LL i = 0; i < n; i++){
y[i] -= m * t * 2 * i;
}
vector<LL> a, b;
for(LL i = k; i >= 0; i--){
a.push_back(y[i]);
}
for(LL i = k; i < n; i++){
b.push_back(y[i]);
}
if(ok(a,b)){
e = m;
} else {
s = m;
}
}
cout << e << '\n';
}
Compilation message
sparklers.cpp: In function 'LL reach(std::vector<long long int>, std::vector<long long int>)':
sparklers.cpp:10:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(LL i = 0; i < a.size(); i++){
~~^~~~~~~~~~
sparklers.cpp:21:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(LL i = 0; i < b.size(); i++){
~~^~~~~~~~~~
sparklers.cpp:32:10: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while(i < acompress.size() - 1 && j < bcompress.size() - 1){
~~^~~~~~~~~~~~~~~~~~~~~~
sparklers.cpp:32:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
while(i < acompress.size() - 1 && j < bcompress.size() - 1){
~~^~~~~~~~~~~~~~~~~~~~~~
sparklers.cpp: In function 'LL ok(std::vector<long long int>, std::vector<long long int>)':
sparklers.cpp:46:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0; i < a.size(); i++){
~~^~~~~~~~~~
sparklers.cpp:47:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 0; j < b.size(); j++){
~~^~~~~~~~~~
sparklers.cpp: In function 'LL okay(std::vector<long long int>, std::vector<long long int>)':
sparklers.cpp:62:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(LL j = 0; j < a.size(); j++){
~~^~~~~~~~~~
sparklers.cpp:65:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(LL j = 0; j < b.size(); j++){
~~^~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
416 KB |
Output is correct |
| 2 |
Correct |
3 ms |
488 KB |
Output is correct |
| 3 |
Correct |
2 ms |
488 KB |
Output is correct |
| 4 |
Correct |
2 ms |
488 KB |
Output is correct |
| 5 |
Correct |
2 ms |
564 KB |
Output is correct |
| 6 |
Correct |
2 ms |
620 KB |
Output is correct |
| 7 |
Correct |
3 ms |
620 KB |
Output is correct |
| 8 |
Correct |
3 ms |
620 KB |
Output is correct |
| 9 |
Correct |
2 ms |
620 KB |
Output is correct |
| 10 |
Correct |
2 ms |
620 KB |
Output is correct |
| 11 |
Correct |
2 ms |
620 KB |
Output is correct |
| 12 |
Correct |
2 ms |
740 KB |
Output is correct |
| 13 |
Correct |
2 ms |
740 KB |
Output is correct |
| 14 |
Correct |
2 ms |
740 KB |
Output is correct |
| 15 |
Correct |
2 ms |
740 KB |
Output is correct |
| 16 |
Correct |
3 ms |
740 KB |
Output is correct |
| 17 |
Correct |
2 ms |
756 KB |
Output is correct |
| 18 |
Correct |
2 ms |
756 KB |
Output is correct |
| 19 |
Correct |
2 ms |
756 KB |
Output is correct |
| 20 |
Correct |
2 ms |
756 KB |
Output is correct |
| 21 |
Correct |
2 ms |
756 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
416 KB |
Output is correct |
| 2 |
Correct |
3 ms |
488 KB |
Output is correct |
| 3 |
Correct |
2 ms |
488 KB |
Output is correct |
| 4 |
Correct |
2 ms |
488 KB |
Output is correct |
| 5 |
Correct |
2 ms |
564 KB |
Output is correct |
| 6 |
Correct |
2 ms |
620 KB |
Output is correct |
| 7 |
Correct |
3 ms |
620 KB |
Output is correct |
| 8 |
Correct |
3 ms |
620 KB |
Output is correct |
| 9 |
Correct |
2 ms |
620 KB |
Output is correct |
| 10 |
Correct |
2 ms |
620 KB |
Output is correct |
| 11 |
Correct |
2 ms |
620 KB |
Output is correct |
| 12 |
Correct |
2 ms |
740 KB |
Output is correct |
| 13 |
Correct |
2 ms |
740 KB |
Output is correct |
| 14 |
Correct |
2 ms |
740 KB |
Output is correct |
| 15 |
Correct |
2 ms |
740 KB |
Output is correct |
| 16 |
Correct |
3 ms |
740 KB |
Output is correct |
| 17 |
Correct |
2 ms |
756 KB |
Output is correct |
| 18 |
Correct |
2 ms |
756 KB |
Output is correct |
| 19 |
Correct |
2 ms |
756 KB |
Output is correct |
| 20 |
Correct |
2 ms |
756 KB |
Output is correct |
| 21 |
Correct |
2 ms |
756 KB |
Output is correct |
| 22 |
Correct |
9 ms |
1532 KB |
Output is correct |
| 23 |
Correct |
6 ms |
1532 KB |
Output is correct |
| 24 |
Correct |
4 ms |
1532 KB |
Output is correct |
| 25 |
Correct |
5 ms |
1532 KB |
Output is correct |
| 26 |
Correct |
11 ms |
1592 KB |
Output is correct |
| 27 |
Correct |
14 ms |
1660 KB |
Output is correct |
| 28 |
Correct |
20 ms |
2556 KB |
Output is correct |
| 29 |
Correct |
20 ms |
2556 KB |
Output is correct |
| 30 |
Correct |
14 ms |
2556 KB |
Output is correct |
| 31 |
Correct |
16 ms |
2556 KB |
Output is correct |
| 32 |
Correct |
20 ms |
2684 KB |
Output is correct |
| 33 |
Correct |
20 ms |
2684 KB |
Output is correct |
| 34 |
Correct |
12 ms |
2684 KB |
Output is correct |
| 35 |
Correct |
17 ms |
2684 KB |
Output is correct |
| 36 |
Correct |
7 ms |
2684 KB |
Output is correct |
| 37 |
Correct |
9 ms |
2684 KB |
Output is correct |
| 38 |
Correct |
18 ms |
2684 KB |
Output is correct |
| 39 |
Correct |
6 ms |
2684 KB |
Output is correct |
| 40 |
Correct |
18 ms |
2684 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
3 ms |
416 KB |
Output is correct |
| 2 |
Correct |
3 ms |
488 KB |
Output is correct |
| 3 |
Correct |
2 ms |
488 KB |
Output is correct |
| 4 |
Correct |
2 ms |
488 KB |
Output is correct |
| 5 |
Correct |
2 ms |
564 KB |
Output is correct |
| 6 |
Correct |
2 ms |
620 KB |
Output is correct |
| 7 |
Correct |
3 ms |
620 KB |
Output is correct |
| 8 |
Correct |
3 ms |
620 KB |
Output is correct |
| 9 |
Correct |
2 ms |
620 KB |
Output is correct |
| 10 |
Correct |
2 ms |
620 KB |
Output is correct |
| 11 |
Correct |
2 ms |
620 KB |
Output is correct |
| 12 |
Correct |
2 ms |
740 KB |
Output is correct |
| 13 |
Correct |
2 ms |
740 KB |
Output is correct |
| 14 |
Correct |
2 ms |
740 KB |
Output is correct |
| 15 |
Correct |
2 ms |
740 KB |
Output is correct |
| 16 |
Correct |
3 ms |
740 KB |
Output is correct |
| 17 |
Correct |
2 ms |
756 KB |
Output is correct |
| 18 |
Correct |
2 ms |
756 KB |
Output is correct |
| 19 |
Correct |
2 ms |
756 KB |
Output is correct |
| 20 |
Correct |
2 ms |
756 KB |
Output is correct |
| 21 |
Correct |
2 ms |
756 KB |
Output is correct |
| 22 |
Correct |
9 ms |
1532 KB |
Output is correct |
| 23 |
Correct |
6 ms |
1532 KB |
Output is correct |
| 24 |
Correct |
4 ms |
1532 KB |
Output is correct |
| 25 |
Correct |
5 ms |
1532 KB |
Output is correct |
| 26 |
Correct |
11 ms |
1592 KB |
Output is correct |
| 27 |
Correct |
14 ms |
1660 KB |
Output is correct |
| 28 |
Correct |
20 ms |
2556 KB |
Output is correct |
| 29 |
Correct |
20 ms |
2556 KB |
Output is correct |
| 30 |
Correct |
14 ms |
2556 KB |
Output is correct |
| 31 |
Correct |
16 ms |
2556 KB |
Output is correct |
| 32 |
Correct |
20 ms |
2684 KB |
Output is correct |
| 33 |
Correct |
20 ms |
2684 KB |
Output is correct |
| 34 |
Correct |
12 ms |
2684 KB |
Output is correct |
| 35 |
Correct |
17 ms |
2684 KB |
Output is correct |
| 36 |
Correct |
7 ms |
2684 KB |
Output is correct |
| 37 |
Correct |
9 ms |
2684 KB |
Output is correct |
| 38 |
Correct |
18 ms |
2684 KB |
Output is correct |
| 39 |
Correct |
6 ms |
2684 KB |
Output is correct |
| 40 |
Correct |
18 ms |
2684 KB |
Output is correct |
| 41 |
Runtime error |
22 ms |
4856 KB |
Execution killed with signal 11 (could be triggered by violating memory limits) |
| 42 |
Halted |
0 ms |
0 KB |
- |
