#include <bits/stdc++.h>
using namespace std;
const int k_N = 200 + 3;
const int k_Mod = 1e9 + 7;
int n, cs, cf;
int dp[k_N][k_N][2][k_N][2];
void fix(int &x){
x = (x >= k_Mod) ? (x - k_Mod) : x;
}
int main(){
ios::sync_with_stdio(false);
cin.tie(NULL);
cin >> n >> cs >> cf;
--cs;
--cf;
for(int left = 0; left <= cf; ++left){
for(int right = 0; right <= n - cf; ++right){
for(int side = 0; side <= 1; ++side){
int cnt = (side ? right : left);
for(int position = 0; position < cnt; ++position){
for(int direction = 0; direction <= 1; ++direction){
int &answer = dp[left][right][side][position][direction];
if(left == 0 && right == 1){
answer = 1;
continue;
}
if(side == 1 && position == 0){
answer = 0;
continue;
}
answer = 0;
if(!side){
if(!direction){
for(int new_position = 0; new_position < position; ++new_position){
answer += dp[left - 1][right][0][new_position][1];
fix(answer);
}
}
else{
for(int new_position = position; new_position < left - 1; ++new_position){
answer += dp[left - 1][right][0][new_position][0];
fix(answer);
}
for(int new_position = 0; new_position < right; ++new_position){
answer += dp[left - 1][right][1][new_position][0];
fix(answer);
}
}
}
else{
if(direction){
for(int new_position = position; new_position < right - 1; ++new_position){
answer += dp[left][right - 1][1][new_position][0];
fix(answer);
}
}
else{
for(int new_position = 0; new_position < position; ++new_position){
answer += dp[left][right - 1][1][new_position][1];
fix(answer);
}
for(int new_position = 0; new_position < left; ++new_position){
answer += dp[left][right - 1][0][new_position][1];
fix(answer);
}
}
}
//cout << dp[left][right][side][position][direction] << " - " << left << " " << right << " " << side << " " << position << " " << direction << endl;
}
}
}
}
}
int answer = 0;
if(cs < cf){
answer += dp[cf][n - cf][0][cs][0];
answer += dp[cf][n - cf][0][cs][1];
}
else{
answer += dp[cf][n - cf][1][cs - cf][0];
answer += dp[cf][n - cf][1][cs - cf][1];
}
fix(answer);
cout << answer << "\n";
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
436 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
436 KB |
Output is correct |
3 |
Correct |
5 ms |
512 KB |
Output is correct |
4 |
Correct |
6 ms |
1408 KB |
Output is correct |
5 |
Correct |
5 ms |
768 KB |
Output is correct |
6 |
Correct |
6 ms |
1792 KB |
Output is correct |
7 |
Correct |
6 ms |
1664 KB |
Output is correct |
8 |
Correct |
5 ms |
896 KB |
Output is correct |
9 |
Correct |
6 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1280 KB |
Output is correct |
11 |
Correct |
5 ms |
1408 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
436 KB |
Output is correct |
3 |
Correct |
5 ms |
512 KB |
Output is correct |
4 |
Correct |
6 ms |
1408 KB |
Output is correct |
5 |
Correct |
5 ms |
768 KB |
Output is correct |
6 |
Correct |
6 ms |
1792 KB |
Output is correct |
7 |
Correct |
6 ms |
1664 KB |
Output is correct |
8 |
Correct |
5 ms |
896 KB |
Output is correct |
9 |
Correct |
6 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1280 KB |
Output is correct |
11 |
Correct |
5 ms |
1408 KB |
Output is correct |
12 |
Correct |
220 ms |
29688 KB |
Output is correct |
13 |
Correct |
124 ms |
19448 KB |
Output is correct |
14 |
Correct |
31 ms |
3576 KB |
Output is correct |
15 |
Correct |
258 ms |
28500 KB |
Output is correct |
16 |
Correct |
19 ms |
2304 KB |
Output is correct |
17 |
Correct |
227 ms |
30540 KB |
Output is correct |
18 |
Correct |
79 ms |
9720 KB |
Output is correct |
19 |
Correct |
226 ms |
30880 KB |
Output is correct |
20 |
Correct |
236 ms |
31608 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
5 ms |
384 KB |
Output is correct |
2 |
Correct |
5 ms |
436 KB |
Output is correct |
3 |
Correct |
5 ms |
512 KB |
Output is correct |
4 |
Correct |
6 ms |
1408 KB |
Output is correct |
5 |
Correct |
5 ms |
768 KB |
Output is correct |
6 |
Correct |
6 ms |
1792 KB |
Output is correct |
7 |
Correct |
6 ms |
1664 KB |
Output is correct |
8 |
Correct |
5 ms |
896 KB |
Output is correct |
9 |
Correct |
6 ms |
1792 KB |
Output is correct |
10 |
Correct |
5 ms |
1280 KB |
Output is correct |
11 |
Correct |
5 ms |
1408 KB |
Output is correct |
12 |
Correct |
220 ms |
29688 KB |
Output is correct |
13 |
Correct |
124 ms |
19448 KB |
Output is correct |
14 |
Correct |
31 ms |
3576 KB |
Output is correct |
15 |
Correct |
258 ms |
28500 KB |
Output is correct |
16 |
Correct |
19 ms |
2304 KB |
Output is correct |
17 |
Correct |
227 ms |
30540 KB |
Output is correct |
18 |
Correct |
79 ms |
9720 KB |
Output is correct |
19 |
Correct |
226 ms |
30880 KB |
Output is correct |
20 |
Correct |
236 ms |
31608 KB |
Output is correct |
21 |
Execution timed out |
2085 ms |
87576 KB |
Time limit exceeded |
22 |
Halted |
0 ms |
0 KB |
- |