CodeForces

https://codeforces.com/problemset/problem/1428/E

是个贪心，真的玄学阿。不太明白是怎么回事。

样例能看出来，肯定不是只把一个分成两份，那就枚举。分成两份的也有机会分成三份，这样就公平了，谁贡献大就分谁

#include<iostream>
#include<queue>
#include<set>
#include<vector>
using namespace std;
const int maxn = 2e5+1;
typedef long long ll;
ll list[maxn];

struct Node{
	ll x,len;
	ll tim;
	Node(ll a,ll b,ll c):x(a),tim(b),len(c){}
};

bool operator < (Node a,Node b){
	return a.len < b.len;
}

priority_queue<Node>que;

ll cal(ll a,ll b){//a分成b个 
	ll cnt = a % b;
	ll x = a/b;
	ll ans = (x*x)*(b - cnt) + ((x+1)*(x+1))*cnt;
	return ans;
} 



int main(){
	int n,k;
	cin>>n>>k;
	ll x;
	ll ans = 0;
	for(int i=1;i<=n;i++){
		cin>>x;
		ans += x*x;
		ll c = cal(x,1) - cal(x,2);
		que.push(Node(x,2,c));
	}
	
	for(int i = 0;i<k - n;i++){
		Node a = que.top();
		que.pop();
		
		ans -= a.len;
		ll c = cal(a.x,a.tim) - cal(a.x,a.tim + 1);
		que.push(Node(a.x,a.tim+1,c));
	}
	cout<<ans<<endl;
	return 0;
}