题解
桶排的思想,累加每个严格递增的序列的长度减一的值。
n = int(input())
a = [int(x) for x in input().split()]
vis = [0] * 1005
for i in range(n):
vis[a[i]] += 1
ans = 0
while n:
num = 0
for i in range(1, 1001):
if vis[i]:
num += 1
vis[i] -= 1
n -= 1
ans += num - 1
print(ans)