// Slower C++ solution:
#pragma once

#include <sstream>

#include <string>

#include <vector>

#include <map>

#include <algorithm>

#include <iostream>

#include <utility>

#include <set>

#include <cctype>

#include <queue>

#include <stack>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <deque>

#include <numeric>

#include <iomanip>

#define M_PI acos(-1)

using namespace std;

typedef long long ll;

typedef pair<int, int> pii;

const int INF = 1000000007;

const int MAX_V = 201;

int now = 0;



const int MAX = 510000;

const int MOD = 1000000007;



long long fac[MAX], finv[MAX], inv[MAX];



// テーブルを作る前処理

void COMinit() {

	fac[0] = fac[1] = 1;

	finv[0] = finv[1] = 1;

	inv[1] = 1;

	for (int i = 2; i < MAX; i++) {

		fac[i] = fac[i - 1] * i % MOD;

		inv[i] = MOD - inv[MOD%i] * (MOD / i) % MOD;

		finv[i] = finv[i - 1] * inv[i] % MOD;

	}

}



// 二項係数計算

long long COM(int n, int k) {

	if (n < k) return 0;

	if (n < 0 || k < 0) return 0;

	return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;

}

struct edge {

	int t;

	ll cost;

	edge(int _t, ll _cost) : t(_t)

		, cost(_cost) {

	}

};



int n, k;



void Solve() {

	cin >> n >> k;

	pair<ll, ll> p[100010];

	ll kind = 0;

	ll sum = 0;

	set<ll> s;

	for (size_t i = 0; i < n; i++)

	{

		cin >> p[i].second >> p[i].first;

		if (!s.count(p[i].second)) kind++;

		s.insert(p[i].second);

		sum += p[i].first;

	}

	sort(p, p + n);

	ll red[100010];

	set<ll> s2;

	ll kind2 = 0;

	ll fd[100010];

	int pi = 0;

	int fi = 0;

	fd[fi++] = 0;

	for (int i = n - 1; i >= 0; i--)

	{

		if (!s2.count(p[i].second)) {

			kind2++;

			fd[fi++] = p[i].first + (kind2 * kind2 - (kind2 - 1) * (kind2 - 1));

			s2.insert(p[i].second);

		}

		else {

			red[pi++] = p[i].first;

		}

	}



	ll res = kind * kind + sum;

	for (size_t i = 0; i < n - k; i++)

	{

		ll fv = fd[fi - 1];

		if (pi > 0 & red[pi - 1] <= fv) {

			res -= red[--pi];

		}

		else { 

			res -= fv;

			fi--;

		}

	}

	cout << res << endl;

}

int main() {

	Solve();

	return 0;

}




// Faster C++ solution for the same problem (measured speedup: 1.4389652129701525x):
#include <stdio.h>

#include <sstream>

#include <string.h>

#include <vector>

#include <map>

#include <algorithm>

#include <utility>

#include <set>

#include <cctype>

#include <queue>

#include <stack>

#include <cstdio>

#include <cstdlib>

#include <cmath>

#include <deque>

#include <limits>

#include <iomanip>

#include <ctype.h>

#include <unordered_map>

#include <random>

#include <numeric>

#include <iostream>

#include <array>



#define _USE_MATH_DEFINES

#include <iostream>

#include <math.h>

using namespace std;

typedef long long ll;

typedef pair<int, int> pii;

typedef pair<ll, ll> pll;

typedef pair<ll, double> pld;

typedef pair<double, double> pdd;

typedef pair<double, ll> pdl;

typedef pair<int, char> pic;

typedef vector<ll> vl;

typedef vector<int> vi;

typedef priority_queue<ll, vector<ll>, greater<ll>> llgreaterq;

typedef priority_queue<pll, vector<pll>, greater<pll>> pllgreaterq;

typedef priority_queue<pair<ll, pll>, vector<pair<ll, pll>>, greater<pair<ll, pll>>> plpllgreaterq;

typedef priority_queue<vi, vector<vi>, greater<vi>> vigreaterq;

typedef priority_queue<vl, vector<vl>, greater<vl >> vlgreaterq;

int dx[] = { -1,0,1,0 };

int dy[] = { 0,-1,0,1 };

#define bit(x,v) ((ll)x << v)

#define rep(x,n) for(int x = 0;x < n;x++)

#define rep2(x,f,v) for(int x=f;x<v;x++)

// 許容する誤差ε

#define EPS (1e-10)

// 2つのスカラーが等しいかどうか

#define EQ(a,b) (std::abs(a-b) < EPS)

// 2つのベクトルが等しいかどうか

#define EQV(a,b) ( EQ((a).real(), (b).real()) && EQ((a).imag(), (b).imag()) )

#define all(a) a.begin(),a.end()

#define all0(a) memset(a,0,sizeof(a))

#define alm1(a) memset(a,-1,sizeof(a))



const ll INF = 1000000007;

const int MAX = 2000010;

const int MOD = 1000000007;



long long fac[MAX], finv[MAX], inv[MAX];

void COMinit() {

	fac[0] = fac[1] = 1;

	finv[0] = finv[1] = 1;

	inv[1] = 1;

	for (int i = 2; i < MAX; i++) {

		fac[i] = fac[i - 1] * i % MOD;

		inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;

		finv[i] = finv[i - 1] * inv[i] % MOD;

	}

}



// 二項係数計算

long long COM(int n, int k) {

	if (n < k) return 0;

	if (n < 0 || k < 0) return 0;

	return fac[n] * (finv[k] * finv[n - k] % MOD) % MOD;

}



ll gcd(ll a, ll b) {

	if (b == 0) return a;

	return gcd(b, a % b);

}

int pr[100010];

int lank[100010];

void uini(int n) {

	for (size_t i = 0; i <= n; i++)

	{

		pr[i] = i;

		lank[i] = 1;

	}

}



int parent(int x) {

	if (x == pr[x]) return x;

	return pr[x] = parent(pr[x]);

}



int same(int x, int y) {

	return parent(x) == parent(y);

}



bool unit(int x, int y) {

	int px = parent(x);

	int py = parent(y);



	if (px == py) return false;

	if (lank[py] < lank[px]) {

		pr[py] = px;

		lank[px] += lank[py];

	}

	else {

		pr[px] = py;

		lank[py] += lank[px];

	}

	return true;

}



ll bit[200010];

int max_n = 200000;

int pm = 0;

void add(int x) {



	while (max_n >= x)

	{

		bit[x]++;

		x += x & -x;

	}

}

void sub(int x) {

	while (max_n >= x)

	{

		bit[x]--;

		x += x & -x;

	}

}

ll merge(ll* a, int left, int mid, int right) {

	ll n1 = mid - left;

	ll n2 = right - mid;

	vector<int> L(n1 + 1);

	vector<int> R(n2 + 1);

	for (size_t i = 0; i < n1; i++)

	{

		L[i] = a[left + i];

	}

	for (size_t i = 0; i < n2; i++)

	{

		R[i] = a[mid + i];

	}



	L[n1] = INF;

	R[n2] = INF;

	ll i = 0;

	ll j = 0;

	ll r = 0;

	for (size_t k = left; k < right; k++)

	{

		if (L[i] <= R[j]) {

			a[k] = L[i];

			i++;

		}

		else {

			a[k] = R[j];

			r += n1 - i;

			j++;

		}

	}

	return r;

}

ll merge2(pair<int, char>* a, int left, int mid, int right) {

	ll n1 = mid - left;

	ll n2 = right - mid;

	vector<pair<int, char>> L(n1 + 1);

	vector<pair<int, char>> R(n2 + 1);

	for (size_t i = 0; i < n1; i++)

	{

		L[i] = a[left + i];

	}

	for (size_t i = 0; i < n2; i++)

	{

		R[i] = a[mid + i];

	}



	L[n1] = make_pair(INF, ' ');

	R[n2] = make_pair(INF, ' ');

	ll i = 0;

	ll j = 0;

	ll r = 0;

	for (size_t k = left; k < right; k++)

	{

		if (L[i].first <= R[j].first) {

			a[k] = L[i];

			i++;

		}

		else {

			a[k] = R[j];

			r += n1 - i;

			j++;

		}

	}

	return r;

}

ll mergeSort2(pair<int, char>* a, int left, int right) {

	ll res = 0;

	if (left + 1 < right) {

		int mid = (left + right) / 2;

		res = mergeSort2(a, left, mid);

		res += mergeSort2(a, mid, right);

		res += merge2(a, left, mid, right);

	}

	return res;

}

ll mergeSort(ll* a, int left, int right) {

	ll res = 0;

	if (left + 1 < right) {

		int mid = (left + right) / 2;

		res = mergeSort(a, left, mid);

		res += mergeSort(a, mid, right);

		res += merge(a, left, mid, right);

	}

	return res;

}

int partition(pair<int, char>* a, int p, int r) {

	pair<int, char> x = a[r];

	int i = p - 1;

	for (size_t j = p; j < r; j++)

	{

		if (a[j].first <= x.first) {

			i++;

			swap(a[i], a[j]);

		}

	}

	swap(a[i + 1], a[r]);

	return i + 1;

}

void quick(pair<int, char>* a, int p, int r) {

	if (p < r) {

		int q = partition(a, p, r);

		quick(a, p, q - 1);

		quick(a, q + 1, r);

	}

}



ll n;

int ci = 0;

ll P[1000010];

struct Node {

	int key;

	int priority;

	Node* parent, * left, * right;

	Node(int key, int priority);

	Node() {}

};

Node NIL;

Node::Node(int key, int priority) : key(key), priority(priority) {

	left = &NIL;

	right = &NIL;

}

Node* root = new Node();

void cenrec(Node* k) {

	if (k->key == NIL.key) return;

	cenrec(k->left);

	cout << " " << k->key;

	cenrec(k->right);

}

void fastrec(Node* k)

{

	if (k->key == NIL.key) return;

	cout << " " << k->key;

	fastrec(k->left);

	fastrec(k->right);

}

void insert(Node* v) {

	Node* y = &NIL;

	Node* x = root;

	while (x->key != NIL.key)

	{

		y = x;

		if (v->key < x->key) {

			x = x->left;

		}

		else {

			x = x->right;

		}

	}

	v->parent = y;

	if (y->key == NIL.key) {

		root = v;

	}

	else if (v->key < y->key) {

		y->left = v;

	}

	else {

		y->right = v;

	}



}



Node* find(Node* k, ll v)

{

	if (k->key == NIL.key) return &NIL;

	if (k->key == v) return k;

	if (v < k->key) return find(k->left, v);

	return find(k->right, v);

}

void delp12(Node* x) {

	if (x->key == NIL.key)  return;

	Node* l = x->left;

	Node* r = x->right;

	Node* pr = x->parent;



	if (l->key == NIL.key

		&& r->key == NIL.key) {

		if (pr->left == x) {

			pr->left = &NIL;

		}

		else pr->right = &NIL;

	}

	else if (l->key != NIL.key) {

		if (pr->left == x) {

			pr->left = l;

		}

		else pr->right = l;

		l->parent = pr;

	}

	else if (r->key != NIL.key) {

		if (pr->left == x) {

			pr->left = r;

		}

		else pr->right = r;

		r->parent = pr;

	}

}

Node* get_next(Node* k) {

	if (k->key == NIL.key) return &NIL;

	Node* res = get_next(k->left);

	if (res->key != NIL.key) return res;

	return k;

}

void del(Node* x) {



	if (x->key == NIL.key) return;

	Node* l = x->left;

	Node* r = x->right;

	Node* pr = x->parent;



	if (l->key != NIL.key && r->key != NIL.key) {

		Node* nex = get_next(r);

		x->key = nex->key;

		delp12(nex);

	}

	else {

		delp12(x);

	}

}

Node* rightRotate(Node* t) {

	Node* s = t->left;

	t->left = s->right;

	s->right = t;

	return s;

}

Node* leftRotate(Node* t) {

	Node* s = t->right;

	t->right = s->left;

	s->left = t;

	return s;

}

Node* _insert(Node* t, int key, int priority) {

	if (t->key == NIL.key) {

		return new Node(key, priority);

	}

	if (key == t->key) {

		return t;

	}



	if (key < t->key) {

		t->left = _insert(t->left, key, priority);

		if (t->priority < t->left->priority) {

			t = rightRotate(t);

		}

	}

	else {

		t->right = _insert(t->right, key, priority);

		if (t->priority < t->right->priority) {

			t = leftRotate(t);

		}

	}

	return t;

}

Node* delete1(Node* t, int key);

Node* _delete(Node* t, int key) {

	if (t->left->key == NIL.key && t->right->key == NIL.key) {

		return &NIL;

	}

	else if (t->left->key == NIL.key) {

		t = leftRotate(t);

	}

	else if (t->right->key == NIL.key) {

		t = rightRotate(t);

	}

	else

	{

		if (t->left->priority > t->right->priority) {

			t = rightRotate(t);

		}

		else

			t = leftRotate(t);

	}

	return delete1(t, key);

}

Node* delete1(Node* t, int key) {

	if (t->key == NIL.key) {

		return &NIL;

	}

	if (key < t->key) {

		t->left = delete1(t->left, key);

	}

	else if (key > t->key) {

		t->right = delete1(t->right, key);

	}

	else return _delete(t, key);

	return t;

}

int H;

int left(int i) {

	return i * 2 + 1;

}

int right(int i) {

	return i * 2 + 2;

}

struct edge {

	int from, to;

	ll val;

	edge(int from, int to, ll val) : from(from), to(to), val(val) {}

};

ll k;

int _rank[1010];

int temp[1010];

bool compare_sa(int i, int j) {

	if (_rank[i] != _rank[j]) return _rank[i] < _rank[j];

	else {

		int ri = i + k <= n ? _rank[i + k] : -1;

		int rj = j + k <= n ? _rank[j + k] : -1;

		return ri < rj;

	}

}

void construct_sa(string S, int* sa) {

	n = S.length();



	for (size_t i = 0; i <= n; i++)

	{

		sa[i] = i;

		_rank[i] = i < n ? S[i] : -1;

	}



	for (k = 1; k <= n; k *= 2)

	{

		sort(sa, sa + n + 1, compare_sa);



		// saはソート後の接尾辞の並びになっている、rankは元の位置のindexを保持したまま、更新されている。

		// ピンとこなかった部分

		temp[sa[0]] = 0;

		for (size_t i = 1; i <= n; i++)

		{

			temp[sa[i]] = temp[sa[i - 1]] + (compare_sa(sa[i - 1], sa[i]) ? 1 : 0);

		}

		for (size_t i = 0; i <= n; i++)

		{

			_rank[i] = temp[i];

		}

	}

}

bool contain(string S, int* sa, string T) {

	int a = 0, b = S.length();

	// sa は 接尾辞が辞書順に並んでいる、入っているのはその位置のインデックス

	while (b - a > 1) {

		int c = (a + b) / 2;

		if (S.compare(sa[c], T.length(), T) < 0) a = c;

		else b = c;

	}

	return S.compare(sa[b], T.length(), T) == 0;

}





#define bit(x,v) ((ll)x << v)



class BIT {



	static const int MAX_N = 500010;

public:

	BIT() { memset(bit, 0, sizeof(bit)); }

	ll bit[MAX_N + 1], n;

	ll sum(int i) {

		ll s = 0;

		while (i > 0)

		{

			s += bit[i];

			i -= i & -i;

		}

		return s;

	}



	void add(int i, int x) {

		while (i <= n)

		{

			bit[i] += x;

			i += i & -i;

		}

	}





};

struct UnionFind {

	vector<int> A;

	UnionFind(int n) : A(n, -1) {}

	int find(int x) {

		if (A[x] < 0) return x;

		return A[x] = find(A[x]);

	}

	void unite(int x, int y) {

		x = find(x), y = find(y);

		if (x == y) return;

		if (A[x] > A[y]) swap(x, y);

		A[x] += A[y];

		A[y] = x;

	}

	int ngroups() {

		int ans = 0;

		for (auto a : A) if (a < 0) ans++;

		return ans;

	}

};

void yes() { cout << "Yes\n"; exit(0); }

void no() { cout << "No\n"; exit(0); }

vector<ll> getp(ll n) {



	vector<ll> res;

	ll a = 2;

	if (n % 2 == 0) {

		res.push_back(2);

		while (n % 2 == 0)n /= 2;

	}



	for (ll i = 3; i * i <= n; i += 2)

	{

		if (n % i == 0) {

			res.push_back(i);

			while (n % i == 0)n /= i;

		}

	}

	if (n != 1) res.push_back(n);

	return res;

}

vector<ll> getp2(ll n) {



	vector<ll> res;

	ll a = 2;

	if (n % 2 == 0) {



		while (n % 2 == 0) { n /= 2; res.push_back(2); }

	}



	for (ll i = 3; i * i <= n; i += 2)

	{

		if (n % i == 0) {



			while (n % i == 0) { n /= i; res.push_back(i); }

		}

	}

	if (n != 1) res.push_back(n);

	return res;

}

vector<pll> getp3(ll n) {

	vector<pll> res;

	ll a = 2;

	int si = 0;

	if (n % 2 == 0) {



		res.push_back(make_pair(2, 0));

		while (n % 2 == 0) { n /= 2; res[si].second++; }

		si++;

	}



	for (ll i = 3; i * i <= n; i += 2)

	{

		if (n % i == 0) {

			res.push_back(make_pair(i, 0));

			while (n % i == 0) { n /= i; res[si].second++; }

			si++;

		}

	}

	if (n != 1) { res.push_back(make_pair(n,1)); }

	return res;

}



vector<ll> getDivisors(ll n) {



	vector<ll> res;

	ll a = 2;

	res.push_back(1);

	for (ll i = 2; i * i <= n; i++)

	{



		if (n % i == 0) {

			res.push_back(i);

			if (n / i != i)

				res.push_back(n / i);

		}

	}

	return res;

}



struct ve {

public:

	vector<ve> child;

	int _t = INF;

	ve(int t) :_t(t) {}

	ve(ve _left, ve _right) {

		_t = _left._t + _right._t;

		child.push_back(_left);

		child.push_back(_right);

	}

	bool operator<(const ve& t) const {

		return _t > t._t;

	}

};



vector<bool> elas(ll n) {

	vector<bool> r(n);

	fill(r.begin(), r.end(), 1);

	r[0] = 0;

	r[1] = 0;

	for (ll i = 2; i * i < n; i++)

	{

		if (!r[i]) continue;

		ll ti = i * 2;

		while (ti < n)

		{

			r[ti] = false;

			ti += i;

		}

	}

	return r;

}

bool isPrime(ll v) {

	for (ll i = 2; i * i <= v; i++)

	{

		if (v % i == 0) return false;

	}

	return true;

}



ll getpow(ll b,ll x, ll md) {



	ll t = b;

	ll res = 1;

	while (x > 0)

	{

		if (x & 1) {

			res *= t;

			res %= md;

		}

		x >>= 1;

		t *= t;

		t %= md;

	}

	return res;

}

ll getpow(ll b, ll x) {



	return getpow(b, x, INF);

}



class SegTree {



public :

	const static int MAX_N = 100010;

	const static int DAT_SIZE = (1 << 18) - 1;

	int N, Q;

	int A[MAX_N];

	

	

	ll data[DAT_SIZE], datb[DAT_SIZE];

	void init(int _n) {

		N = 1;

		while (N < _n) N <<= 1;

		memset(data, 0, sizeof(data));

		memset(datb, 0, sizeof(datb));

	}

	void init(int _n,ll iv) {

		N = 1;

		while (N < _n) N <<= 1;

		rep(i, DAT_SIZE) {

			data[i] = iv;

			datb[i] = iv;

		}

	}

	void add(int a, int b, int x) {

		add(a, b + 1, x, 0, 0, N);

	}

	void add(int a, int b, int x, int k, int l, int r) {

		if (a <= l && r <= b) {

			data[k] += x;

		}

		else if (l < b && a < r) {

			datb[k] += (min(b, r) - max(a, l)) * x;

			add(a, b, x, k * 2 + 1, l, (l + r) / 2);

			add(a, b, x, k * 2 + 2, (l + r)/2, r);

		}

	}



	void change(int a, int b, int x) {

		change(a, b + 1, x, 0, 0, N);

	}

	void change(int a, int b, int x, int k, int l, int r) {

		if (a <= l && r <= b) {

			data[k] = x;

		}

		else if (l < b && a < r) {

			datb[k] = x;

			change(a, b, x, k * 2 + 1, l, (l + r) / 2);

			change(a, b, x, k * 2 + 2, (l + r) / 2, r);

		}

	}



	ll sum(int a, int b) {

		return sum(a, b + 1, 0, 0, N);

	}

	ll sum(int a, int b, int k, int l, int r) {

		if (b <= l || r <= a) {

			return 0;

		}

		if (a <= l && r <= b) {

			return data[k] * (r - l) + datb[k];

		}



		ll res = (min(b, r) - max(a, l)) * data[k];

		res += sum(a, b, k * 2 + 1, l, (l + r) / 2);

		res += sum(a, b, k * 2 + 2, (l + r) / 2, r);

		return res;

	}

};

class Segment;

class Circle;



class Point {

public:

	double x, y;



	Point(double x = 0, double y = 0) :x(x), y(y) {}



	Point operator + (Point p) { return Point(x + p.x, y + p.y); }

	Point operator - (Point p) { return Point(x - p.x, y - p.y); }

	Point operator * (double a) { return Point(a * x, a * y); }

	Point operator / (double a) { return Point(x / a, y /a); }



	double abs() { return sqrt(norm()); }

	double norm() { return x * x + y * y; }



	bool operator < (const Point& p)const {

		return x != p.x ? x < p.x : y < p.y;

	}

	bool operator == (const Point& p) const {

		return fabs(x - p.x) < EPS && fabs(y - p.y) < EPS;

	}

	static double dot(Point a, Point b) {

		return a.x * b.x + a.y * b.y;

	}

	static double cross(Point a, Point b) {

		return a.x * b.y - a.y * b.x;

	}

	static bool isOrthogonal(Point a, Point b) {

		return EQ(dot(a, b), 0.0);

	}

	static bool isOrthogonal(Point a1, Point a2, Point b1, Point b2) {

		return isOrthogonal(a1 - a2, b1 - b2);

	}

	static bool isOrthogonal(Segment s1, Segment s2);



	static bool isPalallel(Point a, Point b) {

		return EQ(cross(a, b), 0.0);

	}

	static bool isPalallel(Point a1, Point a2, Point b1, Point b2) {

		return isPalallel(a1 - a2, b1 - b2);

	}

	static bool isPalallel(Segment s1, Segment s2);



	static const int COUNTER_CLOCKWISE = 1;

	static const int CLOCKWISE = -1;

	static const int ONLINE_BACK = 2;

	static const int ONLINE_FRONT = -2;

	static const int ON_SEGMENT = 0;

	static int ccw(Point p0, Point p1, Point p2) {

		Point a = p1 - p0;

		Point b = p2 - p0;

		if (cross(a, b) > EPS) return COUNTER_CLOCKWISE;

		if (cross(a, b) < -EPS) return CLOCKWISE;

		if (dot(a, b) < -EPS) return ONLINE_BACK;

		if (a.norm() < b.norm()) return ONLINE_FRONT;

		return ON_SEGMENT;

	}



	static bool intersect(Point p1, Point p2, Point p3, Point p4) {

		return (ccw(p1, p2, p3) * ccw(p1, p2, p4) <= 0

			&& ccw(p3, p4, p1) * ccw(p3, p4, p2) <= 0);

	} 

	static bool intersect(Segment s1, Segment s2);

	static Point project(Segment s, Point p);



	static Point reflect(Segment s, Point p);



	static Point getDistance(Point a, Point b) {

		return (a - b).abs();

	}



	static double getDistanceLP(Segment s, Point p);



	static double getDistanceSP(Segment s, Point p);

	

	static double getDistance(Segment s1, Segment s2);



	static Point getIntersection(Segment s1, Segment s2);



	static pair<Point, Point> crossPoints(Circle c, Segment s);



	static int contains(vector<Point> g, Point p) {

		int n = g.size();

		bool x = false;

		rep(i, n) {

			Point a = g[i] - p, b = g[(i + 1) % n] - p;

			// 線の上に載っているか

			if (std::abs(cross(a, b)) < EPS && dot(a, b) < EPS) return 1;



			// pを基準として上下にあるか

			// または外積が正か?(→にあるか)

			if (a.y > b.y) swap(a, b);

			if (a.y < EPS && EPS < b.y && cross(a, b) > EPS) x = !x;

		}

		return x ? 2 : 0;

	}



	static vector<Point> andrewScan(vector<Point> s) {

		vector<Point> u, l;

		if (s.size() < 3) return s;

		sort(all(s));

		u.push_back(s[0]);

		u.push_back(s[1]);

		l.push_back(s[s.size() - 1]);

		l.push_back(s[s.size() - 2]);



		for (int i = 2; i < s.size(); i++) {



			for (int _n = u.size(); _n >= 2 && ccw(u[_n - 2], u[_n - 1], s[i]) > CLOCKWISE; _n--) {

				u.pop_back();

			}

			u.push_back(s[i]);

		}



		for (int i = s.size() - 3; i >= 0; i--) {



			for (int _n = l.size(); _n >= 2 && ccw(l[_n - 2], l[_n - 1], s[i]) > CLOCKWISE; _n--) {

				l.pop_back();

			}

			l.push_back(s[i]);

		}



		reverse(all(l));

		for (int i = u.size() - 2; i >= 1; i--)

		{

			l.push_back(u[i]);

		}



		return l;

	}

};



class Segment {

public:

	Point p1, p2;

	Segment() {}

	Segment(Point p1, Point p2) :p1(p1), p2(p2) {}

	Point p1tp2() {

		return p2 - p1;

	}

	Point p2tp1() {

		return p1 - p2;

	}

	double abs() {

		return std::abs(norm());

	}

	double norm() {

		return (p2 - p1).norm();

	}

};



bool Point::isOrthogonal(Segment s1, Segment s2) {

	return EQ(dot(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);

}

bool Point::isPalallel(Segment s1, Segment s2) {

	return EQ(cross(s1.p2 - s1.p1, s2.p2 - s2.p1), 0.0);

}

bool Point::intersect(Segment s1, Segment s2) {

	return intersect(s1.p1,s1.p2,s2.p1,s2.p2);

}

Point Point::project(Segment s, Point p) {

	Point base = s.p2 - s.p1;

	double r = Point::dot(p - s.p1, base) / base.norm();

	return s.p1 + base * r;

}

Point Point::reflect(Segment s, Point p) {

	return (project(s, p) * 2) - p;

}

double Point::getDistanceLP(Segment s, Point p) {

	return std::abs(cross(s.p2 - s.p1,p-s.p1) / (s.p2 - s.p1).abs());

}

double Point::getDistanceSP(Segment s, Point p) {

	if (dot(s.p2 - s.p1, p - s.p1) < 0.0) return (p - s.p1).abs();

	if (dot(s.p1 - s.p2, p - s.p2) < 0.0) return (p - s.p2).abs();

	return getDistanceLP(s,p);

}

double Point::getDistance(Segment s1, Segment s2) {

	if (intersect(s1, s2)) return 0.0;

	return min({ getDistanceSP(s1,s2.p1),getDistanceSP(s1,s2.p2)

		,getDistanceSP(s2,s1.p1),getDistanceSP(s2,s1.p2) });

}



Point Point::getIntersection(Segment s1, Segment s2) {

	// (s1.p1 - s2.p1).norm()

	auto bs = s1.p2 - s1.p1;

	auto n1 = s2.p1 - s1.p1;

	auto n2 = s2.p2 - s1.p1;

	auto c1 = std::abs(cross(n1, bs)) / bs.norm();

	auto c2 = std::abs(cross(n2, bs)) / bs.norm();

	return s2.p1 + (s2.p2 - s2.p1) *  (c1 / (c1 + c2));

	// c1:c2=t:1-t

	// c2t=(1-t)c1

	// t/(1-t)=c1/(c1+c2)

	// 

}



double arg(Point p) { return atan2(p.y, p.x); }

Point polar(double a, double r) { return Point(cos(r) * a, sin(r) * a); }

class Circle {

public:

	Point c;

	double r;

	Circle(Point c=Point(),double r = 0.0) : c(c),r(r){}

	static pair<Point, Point> getCrossPoints(Circle c1, Circle c2) {

		double d = (c1.c - c2.c).abs(); // 中心点どうしの距離

		double a = acos((c1.r * c1.r + d * d - c2.r * c2.r) / (2 * c1.r * d));

		double t = arg(c2.c - c1.c);

		return make_pair(c1.c + polar(c1.r, t + a), c1.c + polar(c1.r, t - a));



	}

};



pair<Point, Point> Point::crossPoints(Circle c, Segment s) {

	auto pp = project(s, c.c);

	auto f = (pp - c.c).norm();

	auto mu = sqrt(c.r * c.r - f );

	auto e = s.p1tp2() / s.p1tp2().abs();

	return make_pair(pp + e * mu, pp - e * mu);



}



ll divRm(string s, ll x) {



	ll r = 0;

	for (size_t i = 0; i < s.size(); i++)

	{

		r *= 10;

		r += s[i] - '0';

		r %= x;

	}

	return r;

}

ll cmbi(ll x, ll b) {



	ll res = 1;

	for (size_t i = 0; i < b; i++)

	{

		res *= x - i;

		res %= INF;

		res *= inv[b - i];

		res %= INF;

	}

	return res;

}



double digsum(ll x) {

	ll res = 0;

	while (x > 0)

	{

		res += x % 10;

		x /= 10;

	}

	return res;

}



bool maching(char a, char b) {

	return (a == b || a == '?' || b == '?');

}

int getArea(ll x, ll v) {

	for (size_t i = 1; i <= 3; i++)

	{

		if (x < v * i) return i - 1;

	}

}



void solv() {



	ll k;

	cin >> n >> k;

	ll t[100010], d[100010];

	ll ki[100010];

	all0(ki);

	ll x = 0;

	ll su = 0;

	rep(i, n) {

		cin >> t[i] >> d[i];

		su += d[i];

		ki[t[i]]++;

		if (ki[t[i]] == 1)

			x++;

	}



	su += x * x;



	pllgreaterq q;

	priority_queue<ll,vector<ll>,greater<ll>> qq;

	rep(i, n) {

		if (ki[t[i]] == 1) {

			qq.push(d[i]);

		}

		else {

			q.push(make_pair(d[i], i));

		}

	}



	for (ll i = n; i > k; i--)

	{

		ll v = INF * INF;

		int bt = -1;

		ll v1 = INF * INF;

		while (!q.empty())

		{

			auto p = q.top();

			if (ki[t[p.second]] == 1) {

				q.pop();

				qq.push(p.first);

			}

			else {

				bt = p.second;

				v = p.first;

				break;

			}

		}

		if (!qq.empty()) {

			auto p = qq.top();

			v1 = p + (x * x - (x - 1) * (x - 1));

		}

		su -= min(v, v1);

		if (v <= v1) {

			ki[t[bt]]--;

			q.pop();

		}

		else {

			x--;

			qq.pop();

		}

	}

	cout << su << endl;

}

int main() {

	//COMinit();

	solv();

	return 0;

}