| # |
Submission time |
Handle |
Problem |
Language |
Result |
Execution time |
Memory |
| 833815 |
2023-08-22T08:49:03 Z |
CSQ31 |
Chorus (JOI23_chorus) |
C++17 |
|
1 ms |
340 KB |
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define fi first
#define se second
#define sz(a) (int)(a.size())
#define all(a) a.begin(),a.end()
#define lb lower_bound
#define ub upper_bound
#define owo ios_base::sync_with_stdio(0);cin.tie(0);
#define debug(...) fprintf(stderr, __VA_ARGS__),fflush(stderr)
#define time__(d) for(long blockTime = 0; (blockTime == 0 ? (blockTime=clock()) != 0 : false);\
debug("%s time : %.4fs\n", d, (double)(clock() - blockTime) / CLOCKS_PER_SEC))
typedef long long int ll;
typedef long double ld;
typedef pair<ll,ll> PII;
typedef pair<int,int> pii;
typedef vector<vector<int>> vii;
typedef vector<vector<ll>> VII;
ll gcd(ll a,ll b){if(!b)return a;else return gcd(b,a%b);}
const int MAXN = 1e6+5;
int a[MAXN],seg[MAXN],n,k;
ll dp[MAXN],p[MAXN];
struct line{
ll m = 0,c = 0;
int cnt = 0;
line(){}
line(ll _m,ll _c,int _cnt):m(_m),c(_c),cnt(_cnt){}
ll eval(ll x){return m*x+c;}
};
deque<line>hull;
void add(line t){
while(sz(hull)>1){
line a = hull[sz(hull)-2];
line b = hull[sz(hull)-1];
//inter(t,a) >= inter(t,b)
if((t.c - a.c) * (b.m - t.m) >= (a.m - t.m) * (t.c - b.c))hull.pop_back();
else break;
}
hull.push_back(t);
}
ll query(ll x){
while(sz(hull)>1 && hull[1].eval(x) >= hull[0].eval(x)){
hull.pop_front();
}
return hull[0].eval(x);
}
int find(ll x){
hull.clear();
int l = -1;
for(int i=1;i<=n;i++)dp[i] = 1e16;
for(int i=1;i<=n;i++){
while(l+1<i && a[l+1] <= i){
l++;
add(line(l,-p[l]-dp[l],seg[l]));
}
if(l+1==i && a[i] <= i)dp[i] = i*1LL*i - p[i] - query(i) + x;
ll res = l*1LL*i - p[l] - query(i) + x;
if(res > dp[i])dp[i] = res;
seg[i] = seg[hull[0].m]+1;
}
/*cout<<x<<'\n';
for(int i=1;i<=n;i++)cout<<dp[i]<<" ";
cout<<'\n';
for(int i=1;i<=n;i++)cout<<seg[i]<<" ";
*/
cout<<'\n';
return seg[n];
}
int main()
{
owo
string s;
cin>>n>>k>>s;
int cur = 0,nxt = 0;
for(int i=0;i<2*n;i++){
if(s[i] == 'A')cur++;
else a[++nxt] = cur;
}
//for(int i=1;i<=n;i++)cout<<a[i]<<" ";
//cout<<'\n';
for(int i=1;i<=n;i++)p[i] = p[i-1]+a[i];
ll l = 0,r = n*1LL*n;
while(r>=l){
ll m = (l+r)/2;
if(find(m)<k)r = m-1;
else l = m+1;
}
find(r);
cout<<dp[n] - k*1LL*r;
}
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
1 ms |
340 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
