题解 | #游游的元素修改#

简单贪心

t = int(input())
for _ in range(t):
    n,l,r = map(int,input().split())
    line = list(map(int,input().split()))
    if n*l <= sum(line) <= n*r:
        cnt = 0
        a = 0
        b = 0
        for i in line:
            if i < l:
                a += l - i
            elif i > r:
                b += i - r
        cnt += min(a,b)
        cnt += max(a,b) - min(a,b)
        print(cnt)
    else:
        print(-1)