// Criminal
#include<bits/stdc++.h>
using namespace std;
const int N = 1009, Mod = 1e9 + 7;
int n, k, Pw[N], C[N][N];
pair < int , int > dp[2][N][N];
string A, B, D, E;
inline int Diff(string s, string d, int l = n - 1)
{
int Cnt = 0;
for (int i = 0; i < l; i ++)
Cnt += (d[i] != s[i]) ^ (Cnt & 1);
return Cnt;
}
inline int Get(string s, int l)
{
int df1 = Diff(s, D, l);
int df2 = Diff(s, E, l);
int tot = 0;
if (df1 <= k)
{
for (int i = 0; i < l; i ++)
if (s[i] == '1')
tot = (tot + Pw[n - 2 - i] * 1LL * C[k - df1][n - 1 - l]) % Mod;
tot = (tot + Pw[n - 1] * 1LL * C[k - df1][n - 1 - l]) % Mod;
tot = (tot + dp[0][l][k - df1].first) % Mod;
}
if (df2 <= k)
{
for (int i = 0; i < l; i ++)
if (s[i] == '1')
tot = (tot + Pw[n - 2 - i] * 1LL * C[k - df2][n - 1 - l]) % Mod;
tot = (tot + Pw[n - 1] * 1LL * C[k - df2][n - 1 - l]) % Mod;
tot = (tot + dp[1][l][k - df2].first) % Mod;
}
return (tot);
}
int main()
{
ios::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
cin >> n >> k >> D >> A >> B;
A = A.substr(1); B = B.substr(1); E = D;
for (int i = 0; i < (int)D.size(); i ++)
D[i] = (D[i] == 'L' ? '0' : '1'),
E[i] = (E[i] == 'R' ? '0' : '1');
for (int i = Pw[0] = 1; i < N; i ++)
Pw[i] = Pw[i - 1] * 2LL % Mod;
for (int i = 0; i < N; i ++)
for (int j = C[0][i] = C[i][i] = 1; j < i; j ++)
C[j][i] = (C[j][i - 1] + C[j - 1][i - 1]) % Mod;
for (int w = 0; w < 2; w ++)
{
string d = w ? E : D;
dp[w][n - 1][0] = {0, 1};
for (int i = n - 2; ~ i; i --)
for (int j = 0; i + j <= n - 1 && j <= k; j ++)
{
dp[w][i][j].first = dp[w][i + 1][j].first;
dp[w][i][j].second = dp[w][i + 1][j].second;
if (j)
{
dp[w][i][j].first = (dp[w][i][j].first + dp[w][i + 1][j - 1].first) % Mod;
dp[w][i][j].second = (dp[w][i][j].second + dp[w][i + 1][j - 1].second) % Mod;
}
if ((d[i] - '0') ^ (k - j & 1))
dp[w][i][j].first = (dp[w][i][j].first + Pw[n - 2 - i] * 1LL * dp[w][i + 1][j].second) % Mod;
else if (j)
dp[w][i][j].first = (dp[w][i][j].first + Pw[n - 2 - i] * 1LL * dp[w][i + 1][j - 1].second) % Mod;
}
}
if (A == B)
{
if (Diff(A, D) != k && Diff(A, E) != k)
return !printf("0\n");
int tot = 0;
for (int i = 0; i < n - 1; i ++)
if (A[i] == '1')
tot = (tot + Pw[n - 1 - i - 1]) % Mod;
tot = (tot + Pw[n - 1]) % Mod;
return !printf("%d\n", tot);
}
int i = 0;
while (A[i] == B[i])
i ++;
assert(A[i] == '0');
int tot = 0;
if (Diff(A, D) == k || Diff(A, E) == k)
{
for (int i = 0; i < n - 1; i ++)
if (A[i] == '1')
tot = (tot + Pw[n - 1 - i - 1]) % Mod;
tot = (tot + Pw[n - 1]) % Mod;
}
if (Diff(B, D) == k || Diff(B, E) == k)
{
for (int i = 0; i < n - 1; i ++)
if (B[i] == '1')
tot = (tot + Pw[n - 1 - i - 1]) % Mod;
tot = (tot + Pw[n - 1]) % Mod;
}
i ++;
while (i < n - 1)
{
if (A[i] == '0')
{
string s = A;
s[i] = '1';
tot = (tot + Get(s, i + 1)) % Mod;
}
if (B[i] == '1')
{
string s = B;
s[i] = '0';
tot = (tot + Get(s, i + 1)) % Mod;
}
i ++;
}
return !printf("%d\n", tot);
}
Compilation message
ljetopica.cpp: In function 'int main()':
ljetopica.cpp:68:39: warning: suggest parentheses around '-' in operand of '&' [-Wparentheses]
if ((d[i] - '0') ^ (k - j & 1))
~~^~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
12416 KB |
Output is correct |
2 |
Correct |
11 ms |
11776 KB |
Output is correct |
3 |
Correct |
11 ms |
11520 KB |
Output is correct |
4 |
Correct |
10 ms |
11136 KB |
Output is correct |
5 |
Correct |
11 ms |
10752 KB |
Output is correct |
6 |
Correct |
10 ms |
10368 KB |
Output is correct |
7 |
Correct |
11 ms |
9984 KB |
Output is correct |
8 |
Correct |
11 ms |
9600 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
4480 KB |
Output is correct |
2 |
Correct |
8 ms |
4528 KB |
Output is correct |
3 |
Correct |
7 ms |
4480 KB |
Output is correct |
4 |
Correct |
7 ms |
4480 KB |
Output is correct |
5 |
Correct |
7 ms |
4480 KB |
Output is correct |
6 |
Correct |
8 ms |
4608 KB |
Output is correct |
7 |
Correct |
8 ms |
4480 KB |
Output is correct |
8 |
Correct |
7 ms |
4480 KB |
Output is correct |
9 |
Correct |
8 ms |
4480 KB |
Output is correct |
10 |
Correct |
7 ms |
4480 KB |
Output is correct |
11 |
Correct |
7 ms |
4480 KB |
Output is correct |
12 |
Correct |
7 ms |
4480 KB |
Output is correct |
13 |
Correct |
7 ms |
4480 KB |
Output is correct |
14 |
Correct |
8 ms |
4480 KB |
Output is correct |
15 |
Correct |
8 ms |
4608 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
28 ms |
18176 KB |
Output is correct |
2 |
Correct |
27 ms |
17272 KB |
Output is correct |
3 |
Correct |
27 ms |
17792 KB |
Output is correct |
4 |
Correct |
26 ms |
18176 KB |
Output is correct |
5 |
Correct |
24 ms |
17024 KB |
Output is correct |
6 |
Correct |
26 ms |
18176 KB |
Output is correct |
7 |
Correct |
18 ms |
15488 KB |
Output is correct |
8 |
Correct |
26 ms |
17792 KB |
Output is correct |
9 |
Correct |
13 ms |
12672 KB |
Output is correct |
10 |
Correct |
25 ms |
17408 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
11 ms |
12416 KB |
Output is correct |
2 |
Correct |
11 ms |
11776 KB |
Output is correct |
3 |
Correct |
11 ms |
11520 KB |
Output is correct |
4 |
Correct |
10 ms |
11136 KB |
Output is correct |
5 |
Correct |
11 ms |
10752 KB |
Output is correct |
6 |
Correct |
10 ms |
10368 KB |
Output is correct |
7 |
Correct |
11 ms |
9984 KB |
Output is correct |
8 |
Correct |
11 ms |
9600 KB |
Output is correct |
9 |
Correct |
8 ms |
4480 KB |
Output is correct |
10 |
Correct |
8 ms |
4528 KB |
Output is correct |
11 |
Correct |
7 ms |
4480 KB |
Output is correct |
12 |
Correct |
7 ms |
4480 KB |
Output is correct |
13 |
Correct |
7 ms |
4480 KB |
Output is correct |
14 |
Correct |
8 ms |
4608 KB |
Output is correct |
15 |
Correct |
8 ms |
4480 KB |
Output is correct |
16 |
Correct |
7 ms |
4480 KB |
Output is correct |
17 |
Correct |
8 ms |
4480 KB |
Output is correct |
18 |
Correct |
7 ms |
4480 KB |
Output is correct |
19 |
Correct |
7 ms |
4480 KB |
Output is correct |
20 |
Correct |
7 ms |
4480 KB |
Output is correct |
21 |
Correct |
7 ms |
4480 KB |
Output is correct |
22 |
Correct |
8 ms |
4480 KB |
Output is correct |
23 |
Correct |
8 ms |
4608 KB |
Output is correct |
24 |
Correct |
28 ms |
18176 KB |
Output is correct |
25 |
Correct |
27 ms |
17272 KB |
Output is correct |
26 |
Correct |
27 ms |
17792 KB |
Output is correct |
27 |
Correct |
26 ms |
18176 KB |
Output is correct |
28 |
Correct |
24 ms |
17024 KB |
Output is correct |
29 |
Correct |
26 ms |
18176 KB |
Output is correct |
30 |
Correct |
18 ms |
15488 KB |
Output is correct |
31 |
Correct |
26 ms |
17792 KB |
Output is correct |
32 |
Correct |
13 ms |
12672 KB |
Output is correct |
33 |
Correct |
25 ms |
17408 KB |
Output is correct |
34 |
Correct |
25 ms |
18048 KB |
Output is correct |
35 |
Correct |
19 ms |
14848 KB |
Output is correct |
36 |
Correct |
21 ms |
16640 KB |
Output is correct |
37 |
Correct |
20 ms |
17408 KB |
Output is correct |
38 |
Correct |
18 ms |
13312 KB |
Output is correct |
39 |
Correct |
23 ms |
16768 KB |
Output is correct |
40 |
Correct |
16 ms |
13184 KB |
Output is correct |
41 |
Correct |
23 ms |
17920 KB |
Output is correct |
42 |
Correct |
25 ms |
18128 KB |
Output is correct |
43 |
Correct |
24 ms |
17408 KB |
Output is correct |
44 |
Correct |
24 ms |
16640 KB |
Output is correct |
45 |
Correct |
19 ms |
14848 KB |
Output is correct |
46 |
Correct |
23 ms |
17016 KB |
Output is correct |
47 |
Correct |
23 ms |
17152 KB |
Output is correct |
48 |
Correct |
21 ms |
16256 KB |
Output is correct |
49 |
Correct |
15 ms |
12032 KB |
Output is correct |
50 |
Correct |
24 ms |
17792 KB |
Output is correct |
51 |
Correct |
21 ms |
16128 KB |
Output is correct |
52 |
Correct |
22 ms |
16640 KB |
Output is correct |
53 |
Correct |
26 ms |
18176 KB |
Output is correct |
54 |
Correct |
20 ms |
15616 KB |
Output is correct |
55 |
Correct |
25 ms |
18176 KB |
Output is correct |
56 |
Correct |
26 ms |
18176 KB |
Output is correct |
57 |
Correct |
17 ms |
13568 KB |
Output is correct |
58 |
Correct |
25 ms |
18176 KB |
Output is correct |