# | Time | Username | Problem | Language | Result | Execution time | Memory |
---|---|---|---|---|---|---|---|
1017715 | vjudge1 | Feast (NOI19_feast) | C++17 | 0 ms | 0 KiB |
This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
#define F first
#define S second
#define ll long long
#define pii pair<ll,ll>
const int mxN = 3e5 + 5;
const int mod = 1e9 + 7;
using namespace std;
bool operator>(pair<ll,int> a,pair<ll,int>b){
return {a.F,-1 * a.S} > {b.F, -1 * b.S};
}
bool operator<(pair<ll,int> a,pair<ll,int>b){
return {a.F,-1 * a.S} < {b.F, -1 * b.S};
}
int n,k;
int a[mxN];
pair<ll,int> dp[2][2];
pair<ll,int> num;
ll ans;
ll l = 0,r = 1e12,md;
bool solve(){
// cout<<lam<<'\n';
for(int i = 0;i <= 1;i++){
dp[i][0] = {0,0};
dp[i][1] = {0,0};
}
for(int i = 1;i <= n;i++){
// cout<<x<<' '<<(y)<<'\n';
int x = (i & 1),y = (~i & 1);
dp[x][0] = max(dp[(y)][0],dp[(y)][1]);
dp[x][1] = {dp[(y)][0].F + a[i] - md,dp[y][0].S + 1};
if(i > 1) dp[x][1] = max(dp[x][1],{dp[y][1].F + a[i],dp[y][1].S});
// cout<<dp[x][0].F<<' '<<dp[x][0].S<<' '<<dp[x][1].F<<' '<<dp[x][1].S<<'\n';
}
num = max(dp[n & 1][0],dp[n & 1][1]);
// cout<<num.F<<' '<<num.S<<'\n';
return (num.S <= k);
}
signed main(){
cin >>n>>k;
for(int i = 1;i <= n;i++) cin >>a[i];
while(l < r){
md = (l + r) / 2;
if(solve()){
r = md;
ans = num.F + num.S * md;
}else l = md + 1;
}
cout<<ans;
}