1951C - Ticket Hoarding - CodeForces Solution

for _ in range(int(input())):

    def solve():
        n, m, k= map(int, input().split(' '))
        li = list(map(int, input().split(' ')))

        li.sort()
        res = 0
        sofar = 0
        for i in range(n):
            take = min(m, k-sofar)
            res+=(li[i]+sofar)*take
            sofar+=take
        print(res)
    solve()