Buggy python submission (verdict: Runtime Error):
import sys

def solve():
    input = sys.stdin.readline
    N, K = map(int, input().split())
    S = []
    for _ in range(N):
        t, d = map(int, input().split())
        S.append((d, t))
    S.sort(reverse = True)
    upperKCount = 0
    appeared = set()
    maxPoint = 0
    for i in range(K):
        maxPoint += S[i][0]
        if S[i][1] not in appeared:
            upperKCount += 1
            appeared |= {S[i][1]}
    maxPoint += upperKCount ** 2
    appeared = set()

    typeMax = []
    typeNum = 0
    typeLower = []
    others = 0
    for d, t in S:
        if t in appeared: 
            typeLower.append(d)
            others += 1
        else:
            typeMax.append(d)
            typeNum += 1
            appeared |= {t}
    typeMaxSum = [0] * (typeNum + 1)
    typeLowerSum = [0] * (others + 1)
    for i in range(typeNum): typeMaxSum[i+1] = typeMaxSum[i] + typeMax[i]
    for i in range(others): typeLowerSum[i+1] = typeLowerSum[i] + typeLower[i]
    if upperKCount < K:
        for k in range(upperKCount + 1, K+1):
            maxPoint = max(maxPoint, k ** 2 + typeMaxSum[k] + typeLowerSum[K - k])
    print(maxPoint)
    return 0

if __name__ == "__main__":
    solve()

Fixed submission:
import heapq as hq
from collections import deque
from copy import deepcopy
N, K = map(int, input().split())
Sushi = [None for _ in range(N)]
TotalType = set()
for _ in range(N):
    t, d = map(int, input().split())
    Sushi[_] = [d, t]
Sushi.sort(reverse = True)

ChosenType = set()
Double = []
hq.heapify(Double)
BasePoint = 0
for goodsushi in Sushi[:K]:
    BasePoint += goodsushi[0]
    if goodsushi[1] in ChosenType:
        hq.heappush(Double, goodsushi)
    else: ChosenType |= {goodsushi[1]}

NotChosen = deque(deepcopy(Sushi[K:]))
MaxHappiness = BasePoint + len(ChosenType)**2
while Double and NotChosen:
    TrushPoint, TrushType = hq.heappop(Double)
    BasePoint -= TrushPoint
    while NotChosen:
        addPoint, addType = NotChosen.popleft()
        if addType not in ChosenType:
            BasePoint += addPoint
            ChosenType |= {addType}
            break
    MaxHappiness = max(MaxHappiness, BasePoint + len(ChosenType)**2)
print(MaxHappiness)

Buggy python submission (verdict: Runtime Error):
import sys

def solve():
    input = sys.stdin.readline
    N, K = map(int, input().split())
    S = []
    for _ in range(N):
        t, d = map(int, input().split())
        S.append((d, t))
    S.sort(reverse = True)
    upperKCount = 0
    appeared = set()
    maxPoint = 0
    for i in range(K):
        maxPoint += S[i][0]
        if S[i][1] not in appeared:
            upperKCount += 1
            appeared |= {S[i][1]}
    maxPoint += upperKCount ** 2
    appeared = set()

    typeMax = []
    typeNum = 0
    typeLower = []
    others = 0
    for d, t in S:
        if t in appeared: 
            typeLower.append(d)
            others += 1
        else:
            typeMax.append(d)
            typeNum += 1
            appeared |= {t}
    typeMaxSum = [0] * (typeNum + 1)
    typeLowerSum = [0] * (others + 1)
    for i in range(typeNum): typeMaxSum[i+1] = typeMaxSum[i] + typeMax[i]
    for i in range(others): typeLowerSum[i+1] = typeLowerSum[i] + typeLower[i]
    for k in range(upperKCount + 1, K+1):
        maxPoint = max(maxPoint, k ** 2 + typeMaxSum[k] + typeLowerSum[K - k])
    print(maxPoint)
    return 0

if __name__ == "__main__":
    solve()

Fixed submission:
import heapq as hq
from collections import deque
from copy import deepcopy
N, K = map(int, input().split())
Sushi = [None for _ in range(N)]
TotalType = set()
for _ in range(N):
    t, d = map(int, input().split())
    Sushi[_] = [d, t]
Sushi.sort(reverse = True)

ChosenType = set()
Double = []
hq.heapify(Double)
BasePoint = 0
for goodsushi in Sushi[:K]:
    BasePoint += goodsushi[0]
    if goodsushi[1] in ChosenType:
        hq.heappush(Double, goodsushi)
    else: ChosenType |= {goodsushi[1]}

NotChosen = deque(deepcopy(Sushi[K:]))
MaxHappiness = BasePoint + len(ChosenType)**2
while Double and NotChosen:
    TrushPoint, TrushType = hq.heappop(Double)
    BasePoint -= TrushPoint
    while NotChosen:
        addPoint, addType = NotChosen.popleft()
        if addType not in ChosenType:
            BasePoint += addPoint
            ChosenType |= {addType}
            break
    MaxHappiness = max(MaxHappiness, BasePoint + len(ChosenType)**2)
print(MaxHappiness)