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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#488846#8815. Space StationqLWA 61ms7892kbC++14980b2024-07-24 15:43:452024-07-24 15:43:45

Judging History

你现在查看的是最新测评结果

  • [2024-07-30 16:51:06]
  • hack成功,自动添加数据
  • (/hack/760)
  • [2024-07-24 15:43:45]
  • 评测
  • 测评结果:WA
  • 用时:61ms
  • 内存:7892kb
  • [2024-07-24 15:43:45]
  • 提交

answer

#include <cstdio>
using i32 = int;
using i64 = long long;
constexpr i32 N = 100, A = 100;
constexpr i32 mod = 998244353;
i32 n, m;
i32 f[N + 1][A * N + 1];
i32 binom[N + 1][N + 1];
i64 qpow(i64 x, i64 p) noexcept {
	i64 r = 1;
	for (; p; p >>= 1, (x *= x) %= mod)
		if (p & 1) (r *= x) %= mod;
	return r;
}
signed main() noexcept {
	scanf("%d%d", &n, &m);
	for (i32 i = 0; i <= n; ++i) {
		binom[i][0] = 1;
		for (i32 j = 1; j <= i; ++j) binom[i][j] = (binom[i - 1][j - 1] + binom[i - 1][j]) % mod;
	}
	f[0][0] = 1;
	for (i32 i = 1, a; i <= n; ++i) {
		scanf("%d", &a);
		for (i32 j = i; j; --j)
			for (i32 v = a; v <= n * A; ++v) (f[j][v] += f[j - 1][v - a]) %= mod;
	}
	i64 ans = 0;
	for (i32 i = 1; i <= n; ++i) {
		i64 pick = qpow(binom[n][i], mod - 2), invi = qpow(i, mod - 2);
		for (i32 sum = 0; sum <= n * A; ++sum)
			(ans += (sum < m * i ? sum * invi % mod : m) * pick % mod * f[i][sum]) %= mod;
	}
	printf("%lld\n", ans);
	return 0;
}

Details

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Test #1:

score: 100
Accepted
time: 0ms
memory: 3776kb

input:

3 3
2 3 4

output:

499122185

result:

ok 1 number(s): "499122185"

Test #2:

score: 0
Accepted
time: 0ms
memory: 3836kb

input:

5 1
10 20 30 40 50

output:

5

result:

ok 1 number(s): "5"

Test #3:

score: 0
Accepted
time: 0ms
memory: 3884kb

input:

1 9
37

output:

9

result:

ok 1 number(s): "9"

Test #4:

score: 0
Accepted
time: 0ms
memory: 3828kb

input:

5 5
24 41 29 6 40

output:

25

result:

ok 1 number(s): "25"

Test #5:

score: 0
Accepted
time: 1ms
memory: 3996kb

input:

10 34
91 86 1 14 98 13 85 64 91 20

output:

707882334

result:

ok 1 number(s): "707882334"

Test #6:

score: 0
Accepted
time: 61ms
memory: 7892kb

input:

100 9
83 99 170 80 174 137 1 91 111 35 69 39 148 76 142 90 105 30 114 176 196 85 26 109 162 167 171 148 169 162 159 3 4 6 33 61 163 7 77 63 8 20 13 51 26 11 149 136 134 187 96 95 113 104 128 48 167 74 18 91 200 62 167 32 5 180 189 39 63 111 68 72 81 128 42 13 57 180 111 91 83 177 34 45 158 29 114 33...

output:

82380556

result:

ok 1 number(s): "82380556"

Test #7:

score: -100
Wrong Answer
time: 61ms
memory: 7736kb

input:

100 33
24 157 144 142 151 8 93 54 189 74 12 129 77 95 59 13 159 48 67 116 174 194 9 166 170 84 136 68 39 181 133 190 37 115 42 95 134 148 91 59 130 1 68 48 14 126 193 50 192 196 44 85 37 96 66 39 180 129 22 2 17 101 45 159 171 68 113 142 197 156 63 96 185 108 72 69 144 33 115 142 139 11 57 76 126 19...

output:

621942902

result:

wrong answer 1st numbers differ - expected: '516465986', found: '621942902'