abc306e <mutiset的使用>

https://atcoder.jp/contests/abc306/tasks/abc306_e

#include <iostream>
#include <algorithm>
#include <set>
using namespace std;
typedef long long LL;
const int N = 5e5 + 10;
int a[N];
int n, k, q;
multiset<int> X, Y;
LL s;

void balance()
{
    while (X.size() < k)
    {
        auto yp = Y.end(); yp --;
        X.insert(*yp);
        s += *yp;
        Y.erase(yp);
    }
    if (X.size()==0 || Y.size()==0) return;

    while (true)
    {
        auto xp = X.begin();
        auto yp = Y.end(); yp --;
        if (*xp >= *yp) return;
        s += (*yp) - (*xp);
        X.insert(*yp);
        Y.insert(*xp);
        X.erase(xp);
        Y.erase(yp);
    }
}

void add(int x)
{
    Y.insert(x);
    balance();
}

void del(int x)
{
    if (X.find(x) != X.end())
    {
        X.erase(X.find(x));
        s -= x;
    }
    else
    {
        Y.erase(Y.find(x));
    }
    balance();
}


void solv()
{
    cin >> n >> k >> q;
    for (int i = 0; i < k; i ++) X.insert(0);
    for (int i = k; i < n; i ++) Y.insert(0);
    s = 0;

    for (int i = 0; i < q; i ++)
    {
        
        int x, y;
        cin >> x >> y;
        x --;
        add(y);
        del(a[x]);
        cout << s << endl;
        a[x] = y;
    }
    

}

int main()
{
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int T = 1;
    // cin >> T;
    while (T --)
    {
        solv();
    }
    return 0;
}