Submission #33878262

Source Code Expand

MOD = 998244353
N,K = map(int,input().split())
A = sorted(list(map(int,input().split())))
A.insert(0,0)
B1 = [1 for _ in range(N+1)]
for i in range(1,N+1):
    B1[i] = (B1[i-1]*i)%MOD
B2 = [1 for _ in range(N+1)]
B2[N] = pow(B1[N],MOD-2,MOD)
for i in range(N-1,1,-1):
    B2[i] = (B2[i+1]*(i+1))%MOD
def f(n,k):
    if k<0 or k>n:
        return 0
    if k==0 or k==n:
        return 1
    return (B1[n]*B2[k]*B2[n-k])%MOD
ans = 0
for i in range(K,N+1):
    ans = (ans+f(i-1,K-1)*A[i])%MOD
for i in range(N-K+1,0,-1):
    ans = (ans-f(N-i,K-1)*A[i])%MOD
ans = (ans*B1[K]*B1[N-K]*B2[N])%MOD
print(ans)

Submission Info

Submission Time
Task J - Expected Range
User flippergo
Language PyPy3 (7.3.0)
Score 6
Code Size 623 Byte
Status AC
Exec Time 186 ms
Memory 124936 KiB

Judge Result

Set Name Sample All
Score / Max Score 0 / 0 6 / 6
Status
AC × 3
AC × 34
Set Name Test Cases
Sample sample_00.txt, sample_01.txt, sample_02.txt
All case_00.txt, case_01.txt, case_02.txt, case_03.txt, case_04.txt, case_05.txt, case_06.txt, case_07.txt, case_08.txt, case_09.txt, case_10.txt, case_11.txt, case_12.txt, case_13.txt, case_14.txt, case_15.txt, case_16.txt, case_17.txt, case_18.txt, case_19.txt, case_20.txt, case_21.txt, case_22.txt, case_23.txt, case_24.txt, case_25.txt, case_26.txt, case_27.txt, case_28.txt, case_29.txt, case_30.txt, sample_00.txt, sample_01.txt, sample_02.txt
Case Name Status Exec Time Memory
case_00.txt AC 186 ms 124748 KiB
case_01.txt AC 172 ms 124792 KiB
case_02.txt AC 172 ms 124508 KiB
case_03.txt AC 175 ms 124672 KiB
case_04.txt AC 175 ms 124892 KiB
case_05.txt AC 172 ms 124784 KiB
case_06.txt AC 174 ms 124684 KiB
case_07.txt AC 173 ms 124936 KiB
case_08.txt AC 173 ms 124832 KiB
case_09.txt AC 177 ms 124804 KiB
case_10.txt AC 132 ms 116996 KiB
case_11.txt AC 58 ms 68984 KiB
case_12.txt AC 81 ms 83320 KiB
case_13.txt AC 56 ms 69624 KiB
case_14.txt AC 101 ms 95452 KiB
case_15.txt AC 117 ms 105264 KiB
case_16.txt AC 170 ms 118436 KiB
case_17.txt AC 123 ms 110204 KiB
case_18.txt AC 102 ms 90456 KiB
case_19.txt AC 76 ms 80032 KiB
case_20.txt AC 113 ms 97392 KiB
case_21.txt AC 75 ms 78352 KiB
case_22.txt AC 123 ms 110024 KiB
case_23.txt AC 102 ms 96520 KiB
case_24.txt AC 60 ms 67412 KiB
case_25.txt AC 87 ms 87432 KiB
case_26.txt AC 139 ms 117616 KiB
case_27.txt AC 161 ms 110612 KiB
case_28.txt AC 99 ms 88704 KiB
case_29.txt AC 81 ms 85272 KiB
case_30.txt AC 47 ms 62060 KiB
sample_00.txt AC 50 ms 62060 KiB
sample_01.txt AC 48 ms 61860 KiB
sample_02.txt AC 49 ms 61820 KiB