QOJ.ac
QOJ
| ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
|---|---|---|---|---|---|---|---|---|---|
| #228506 | #7642. Integer Half-Sum | ucup-team022# | AC ✓ | 0ms | 3692kb | C++17 | 948b | 2023-10-28 13:38:14 | 2023-10-28 13:38:14 |
Judging History
answer
#include <bits/stdc++.h>
using namespace std;
const int mod = 998244353;
int n, m, jc[1000005], ny[1000005];
int C(int x, int y) {
if (x < y || y < 0 || x < 0) return 0;
return 1ll * jc[x] * ny[y] % mod * ny[x - y] % mod;
}
int Power(int x, int y) {
int r = 1;
while (y) {
if (y & 1) r = 1ll * r * x % mod;
x = 1ll * x * x % mod, y >>= 1;
}
return r;
}
int main() {
int l, r;
cin >> l >> r;
if (r == l + 1) cout << -1;
else if (r == l) cout << r;
else cout << r - 1;
return 0;
cin >> n >> m;
jc[0] = ny[0] = 1;
for (int i = 1; i <= 1000000; i++) jc[i] = 1ll * jc[i - 1] * i % mod;
ny[1000000] = Power(jc[1000000], mod - 2);
for (int i = 1000000 - 1; i; i--) ny[i] = 1ll * ny[i + 1] * (i + 1) % mod;
int ans = 0;
for (int i = 0; i <= m; i++) {
for (int j = 0; j <= n - 1; j++) {
ans = (ans + 1ll * C(n - 1, j) * C(m - i, j) % mod * C(n - j + i - 1, i - 1)) % mod;
}
}
cout << ans;
}
Details
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Test #1:
score: 100
Accepted
time: 0ms
memory: 3496kb
input:
2 4
output:
3
result:
ok 1 number(s): "3"
Test #2:
score: 0
Accepted
time: 0ms
memory: 3600kb
input:
1 1
output:
1
result:
ok 1 number(s): "1"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3660kb
input:
1 2
output:
-1
result:
ok 1 number(s): "-1"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3536kb
input:
100 100
output:
100
result:
ok 1 number(s): "100"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3532kb
input:
99 100
output:
-1
result:
ok 1 number(s): "-1"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3624kb
input:
3 3
output:
3
result:
ok 1 number(s): "3"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3592kb
input:
2 3
output:
-1
result:
ok 1 number(s): "-1"
Test #8:
score: 0
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time: 0ms
memory: 3540kb
input:
1 3
output:
2
result:
ok 1 number(s): "2"
Test #9:
score: 0
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time: 0ms
memory: 3680kb
input:
2 5
output:
4
result:
ok 1 number(s): "4"
Test #10:
score: 0
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time: 0ms
memory: 3664kb
input:
3 7
output:
6
result:
ok 1 number(s): "6"
Test #11:
score: 0
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time: 0ms
memory: 3536kb
input:
3 8
output:
7
result:
ok 1 number(s): "7"
Test #12:
score: 0
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time: 0ms
memory: 3688kb
input:
4 10
output:
9
result:
ok 1 number(s): "9"
Test #13:
score: 0
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time: 0ms
memory: 3500kb
input:
35 37
output:
36
result:
ok 1 number(s): "36"
Test #14:
score: 0
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time: 0ms
memory: 3608kb
input:
43 46
output:
45
result:
ok 1 number(s): "45"
Test #15:
score: 0
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time: 0ms
memory: 3660kb
input:
82 86
output:
85
result:
ok 1 number(s): "85"
Test #16:
score: 0
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time: 0ms
memory: 3608kb
input:
55 60
output:
59
result:
ok 1 number(s): "59"
Test #17:
score: 0
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time: 0ms
memory: 3492kb
input:
25 31
output:
30
result:
ok 1 number(s): "30"
Test #18:
score: 0
Accepted
time: 0ms
memory: 3496kb
input:
37 44
output:
43
result:
ok 1 number(s): "43"
Test #19:
score: 0
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time: 0ms
memory: 3608kb
input:
75 83
output:
82
result:
ok 1 number(s): "82"
Test #20:
score: 0
Accepted
time: 0ms
memory: 3664kb
input:
74 83
output:
82
result:
ok 1 number(s): "82"
Test #21:
score: 0
Accepted
time: 0ms
memory: 3608kb
input:
88 98
output:
97
result:
ok 1 number(s): "97"
Test #22:
score: 0
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time: 0ms
memory: 3608kb
input:
75 86
output:
85
result:
ok 1 number(s): "85"
Test #23:
score: 0
Accepted
time: 0ms
memory: 3604kb
input:
1 100
output:
99
result:
ok 1 number(s): "99"
Test #24:
score: 0
Accepted
time: 0ms
memory: 3604kb
input:
1 50
output:
49
result:
ok 1 number(s): "49"
Test #25:
score: 0
Accepted
time: 0ms
memory: 3668kb
input:
50 100
output:
99
result:
ok 1 number(s): "99"
Test #26:
score: 0
Accepted
time: 0ms
memory: 3532kb
input:
7 35
output:
34
result:
ok 1 number(s): "34"
Test #27:
score: 0
Accepted
time: 0ms
memory: 3656kb
input:
87 95
output:
94
result:
ok 1 number(s): "94"
Test #28:
score: 0
Accepted
time: 0ms
memory: 3496kb
input:
11 30
output:
29
result:
ok 1 number(s): "29"
Test #29:
score: 0
Accepted
time: 0ms
memory: 3520kb
input:
47 69
output:
68
result:
ok 1 number(s): "68"
Test #30:
score: 0
Accepted
time: 0ms
memory: 3532kb
input:
11 48
output:
47
result:
ok 1 number(s): "47"
Test #31:
score: 0
Accepted
time: 0ms
memory: 3676kb
input:
71 85
output:
84
result:
ok 1 number(s): "84"
Test #32:
score: 0
Accepted
time: 0ms
memory: 3472kb
input:
84 89
output:
88
result:
ok 1 number(s): "88"
Test #33:
score: 0
Accepted
time: 0ms
memory: 3636kb
input:
22 56
output:
55
result:
ok 1 number(s): "55"
Test #34:
score: 0
Accepted
time: 0ms
memory: 3592kb
input:
2 72
output:
71
result:
ok 1 number(s): "71"
Test #35:
score: 0
Accepted
time: 0ms
memory: 3604kb
input:
18 55
output:
54
result:
ok 1 number(s): "54"
Test #36:
score: 0
Accepted
time: 0ms
memory: 3496kb
input:
4 11
output:
10
result:
ok 1 number(s): "10"
Test #37:
score: 0
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time: 0ms
memory: 3532kb
input:
42 59
output:
58
result:
ok 1 number(s): "58"
Test #38:
score: 0
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time: 0ms
memory: 3532kb
input:
52 79
output:
78
result:
ok 1 number(s): "78"
Test #39:
score: 0
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time: 0ms
memory: 3680kb
input:
11 48
output:
47
result:
ok 1 number(s): "47"
Test #40:
score: 0
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time: 0ms
memory: 3540kb
input:
4 51
output:
50
result:
ok 1 number(s): "50"
Test #41:
score: 0
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time: 0ms
memory: 3536kb
input:
3 60
output:
59
result:
ok 1 number(s): "59"
Test #42:
score: 0
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time: 0ms
memory: 3628kb
input:
21 88
output:
87
result:
ok 1 number(s): "87"
Test #43:
score: 0
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time: 0ms
memory: 3588kb
input:
17 94
output:
93
result:
ok 1 number(s): "93"
Test #44:
score: 0
Accepted
time: 0ms
memory: 3692kb
input:
11 98
output:
97
result:
ok 1 number(s): "97"
Test #45:
score: 0
Accepted
time: 0ms
memory: 3688kb
input:
2 99
output:
98
result:
ok 1 number(s): "98"
Extra Test:
score: 0
Extra Test Passed