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QOJ
ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#380420 | #5532. Kangaroo | nhuang685# | 51 | 875ms | 12036kb | C++20 | 2.0kb | 2024-04-07 03:30:18 | 2024-07-04 03:33:32 |
Judging History
answer
#include <bits/stdc++.h>
const int MOD = (int)1e9 + 7;
struct Mint {
int val;
Mint(int v = 0) : val((v % MOD + MOD) % MOD) {}
Mint &operator+=(Mint b) {
val += b.val;
if (val >= MOD) {
val -= MOD;
}
return *this;
}
Mint &operator-=(Mint b) {
val -= b.val;
if (val < 0) {
val += MOD;
}
return *this;
}
};
Mint operator+(Mint a, Mint b) { return a += b; }
Mint operator-(Mint a, Mint b) { return a -= b; }
Mint psum(int l, int r, int p, std::vector<std::array<Mint, 2>> &v) {
if (l > r) {
return 0;
}
return v[r][p] - v[l - 1][p];
}
int main() {
std::cin.tie(nullptr)->sync_with_stdio(false);
#ifdef LOCAL
std::freopen("input.txt", "r", stdin);
std::freopen("output.txt", "w", stdout);
#endif
int n, cs, cf;
std::cin >> n >> cs >> cf;
// std::vector dp(n + 1, std::vector(n + 1, std::vector(n + 1, std::array<Mint, 2>{0, 0})));
std::vector cur(n + 1, std::vector(n + 1, std::array<Mint, 2>{0, 0}));
std::vector pre = cur;
pre[1][1][0] = pre[1][1][1] = 1;
for (int i = 2; i <= n; ++i) {
for (int st = 1; st <= i; ++st) {
for (int fi = 1; fi < st; ++fi) {
cur[st][fi][0] = psum(fi, i - 1, 1, pre[st - 1]);
cur[st][fi][1] = psum(1, fi - 1, 0, pre[st - 1]);
}
for (int fi = st + 1; fi <= i; ++fi) {
cur[st][fi][0] = psum(fi, i - 1, 1 , pre[st]);
cur[st][fi][1] = psum(1, fi - 1, 0, pre[st]);
}
if (i < n) {
for (int fi = 1; fi <= i; ++fi) {
for (int p : {0, 1}) {
cur[st][fi][p] += cur[st][fi - 1][p];
}
}
}
}
pre = cur;
cur.assign(n + 1, std::vector(n + 1, std::array<Mint, 2>{0, 0}));
}
std::cout << (pre[cs][cf][0] + pre[cs][cf][1]).val << '\n';
}
Details
Tip: Click on the bar to expand more detailed information
Subtask #1:
score: 6
Accepted
Test #1:
score: 6
Accepted
time: 0ms
memory: 3840kb
input:
7 3 6
output:
14
result:
ok 1 number(s): "14"
Subtask #2:
score: 30
Accepted
Dependency #1:
100%
Accepted
Test #2:
score: 30
Accepted
time: 0ms
memory: 3648kb
input:
39 36 32
output:
964903316
result:
ok 1 number(s): "964903316"
Test #3:
score: 0
Accepted
time: 0ms
memory: 3828kb
input:
26 1 26
output:
955348527
result:
ok 1 number(s): "955348527"
Test #4:
score: 0
Accepted
time: 0ms
memory: 3532kb
input:
40 11 33
output:
695661890
result:
ok 1 number(s): "695661890"
Test #5:
score: 0
Accepted
time: 0ms
memory: 3884kb
input:
39 39 38
output:
717149364
result:
ok 1 number(s): "717149364"
Test #6:
score: 0
Accepted
time: 0ms
memory: 3624kb
input:
40 10 25
output:
912929610
result:
ok 1 number(s): "912929610"
Test #7:
score: 0
Accepted
time: 0ms
memory: 3840kb
input:
37 25 23
output:
250748685
result:
ok 1 number(s): "250748685"
Test #8:
score: 0
Accepted
time: 0ms
memory: 3528kb
input:
39 2 38
output:
624060592
result:
ok 1 number(s): "624060592"
Test #9:
score: 0
Accepted
time: 0ms
memory: 3620kb
input:
40 18 22
output:
739993796
result:
ok 1 number(s): "739993796"
Test #10:
score: 0
Accepted
time: 0ms
memory: 3680kb
input:
40 11 35
output:
135213497
result:
ok 1 number(s): "135213497"
Subtask #3:
score: 15
Accepted
Dependency #1:
100%
Accepted
Dependency #2:
100%
Accepted
Test #11:
score: 15
Accepted
time: 10ms
memory: 3852kb
input:
199 100 70
output:
914653136
result:
ok 1 number(s): "914653136"
Test #12:
score: 0
Accepted
time: 11ms
memory: 3972kb
input:
187 3 40
output:
928785584
result:
ok 1 number(s): "928785584"
Test #13:
score: 0
Accepted
time: 13ms
memory: 3832kb
input:
199 198 197
output:
38412688
result:
ok 1 number(s): "38412688"
Test #14:
score: 0
Accepted
time: 13ms
memory: 3908kb
input:
200 40 140
output:
367088143
result:
ok 1 number(s): "367088143"
Test #15:
score: 0
Accepted
time: 13ms
memory: 3872kb
input:
199 111 3
output:
870834793
result:
ok 1 number(s): "870834793"
Test #16:
score: 0
Accepted
time: 13ms
memory: 3996kb
input:
200 133 73
output:
343127012
result:
ok 1 number(s): "343127012"
Test #17:
score: 0
Accepted
time: 9ms
memory: 3676kb
input:
178 15 163
output:
160852284
result:
ok 1 number(s): "160852284"
Test #18:
score: 0
Accepted
time: 12ms
memory: 3824kb
input:
197 43 79
output:
332057544
result:
ok 1 number(s): "332057544"
Test #19:
score: 0
Accepted
time: 13ms
memory: 3924kb
input:
200 33 79
output:
742545318
result:
ok 1 number(s): "742545318"
Subtask #4:
score: 0
Time Limit Exceeded
Dependency #1:
100%
Accepted
Dependency #2:
100%
Accepted
Dependency #3:
100%
Accepted
Test #20:
score: 49
Accepted
time: 596ms
memory: 10064kb
input:
658 169 438
output:
206087110
result:
ok 1 number(s): "206087110"
Test #21:
score: 0
Accepted
time: 710ms
memory: 10692kb
input:
700 207 509
output:
478311263
result:
ok 1 number(s): "478311263"
Test #22:
score: 0
Accepted
time: 875ms
memory: 12036kb
input:
755 139 507
output:
103783948
result:
ok 1 number(s): "103783948"
Test #23:
score: -49
Time Limit Exceeded
input:
2000 500 1500