답안 #117675

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
117675 2019-06-17T05:54:25 Z 송준혁(#2882) Ljetopica (COI19_ljetopica) C++14
100 / 100
71 ms 22264 KB
#include <bits/stdc++.h>
#define MOD 1000000007
using namespace std;
typedef long long LL;
typedef pair<LL, LL> pii;

int N, K;
int P[1010], now[1010];
int A[1010], B[1010];
LL C[1010][1010];
LL D1[1010][1010];
LL D2[1010][1010];
bool chk1[1010][1010];
bool chk2[1010][1010];
LL twoPow[1010], ans;

LL comb(int n, int r){
    if (n < r || r < 0) return 0;
    if (n == r || r == 0) return 1;
    if (C[n][r]) return C[n][r];
    return C[n][r] = (comb(n-1, r-1) + comb(n-1, r)) % MOD;
}

pii f1(int lv, int k, bool l, bool r){
    if (l && now[lv] < A[lv]) return pii(0, 0);
    if (now[lv] > A[lv]) l = false;
    if (r && now[lv] > B[lv]) return pii(0, 0);
    if (now[lv] < B[lv]) r = false;
    if (lv >= N){
        if (k == K) return pii(0, 1);
        return pii(0, 0);
    }

    if (!l && !r && chk1[lv][k]) return pii(D1[lv][k], comb(N-lv, K-k));
    LL t = 0;
    pii ret1, ret2;
    now[lv+1] = P[lv+1] ^ ((K-k) & 1);
    ret1 = f1(lv+1, k, l, r);
    now[lv+1] = P[lv+1] ^ ((K-k-1) & 1);
    ret2 = f1(lv+1, k+1, l, r);
    if (P[lv+1] ^ ((K-k) & 1)) t = (t + ret1.second * twoPow[N-lv-1]) % MOD;
    else t = (t + ret2.second * twoPow[N-lv-1]) % MOD;
    t = (t + ret1.first + ret2.first) % MOD;
    if (!l && !r){
        chk1[lv][k] = true;
        D1[lv][k] = t;
    }
    return pii(t, (ret1.second + ret2.second)%MOD);
}

pii f2(int lv, int k, bool l, bool r){
    if (l && now[lv] < A[lv]) return pii(0, 0);
    if (now[lv] > A[lv]) l = false;
    if (r && now[lv] > B[lv]) return pii(0, 0);
    if (now[lv] < B[lv]) r = false;
    if (lv >= N){
        if (k == K) return pii(0, 1);
        return pii(0, 0);
    }

    if (!l && !r && chk2[lv][k]) return pii(D2[lv][k], comb(N-lv, K-k));
    LL t = 0;
    pii ret1, ret2;
    now[lv+1] = P[lv+1] ^ ((K-k-1) & 1);
    ret1 = f2(lv+1, k, l, r);
    now[lv+1] = P[lv+1] ^ ((K-k) & 1);
    ret2 = f2(lv+1, k+1, l, r);
    if (P[lv+1] ^ ((K-k-1) & 1)) t = (t + ret1.second * twoPow[N-lv-1]) % MOD;
    else t = (t + ret2.second * twoPow[N-lv-1]) % MOD;
    t = (t + ret1.first + ret2.first) % MOD;
    if (!l && !r){
        chk2[lv][k] = true;
        D2[lv][k] = t;
    }
    return pii(t, (ret1.second + ret2.second) % MOD);
}

int main(){
    char ch;
    scanf("%d %d", &N, &K);
    for (int i=2; i<=N; i++){
        scanf(" %c", &ch);
        if (ch == 'R') P[i] = 1;
    }
    for (int i=1; i<=N; i++) scanf("%1d", &A[i]);
    for (int i=1; i<=N; i++) scanf("%1d", &B[i]);
    twoPow[0] = 1;
    for (int i=1; i<=N; i++) twoPow[i] = (twoPow[i-1] * 2) % MOD;
    now[1] = 1;
    pii ret1 = f1(1, 0, true, true);
    pii ret2 = f2(1, 0, true, true);
    printf("%lld\n", (ret1.first + ret1.second*twoPow[N-1] + ret2.first + ret2.second*twoPow[N-1]) % MOD);
    return 0;
}

Compilation message

ljetopica.cpp: In function 'int main()':
ljetopica.cpp:80:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &N, &K);
     ~~~~~^~~~~~~~~~~~~~~~~
ljetopica.cpp:82:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf(" %c", &ch);
         ~~~~~^~~~~~~~~~~~
ljetopica.cpp:85:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (int i=1; i<=N; i++) scanf("%1d", &A[i]);
                              ~~~~~^~~~~~~~~~~~~~
ljetopica.cpp:86:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     for (int i=1; i<=N; i++) scanf("%1d", &B[i]);
                              ~~~~~^~~~~~~~~~~~~~
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 2 ms 384 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 22 ms 10872 KB Output is correct
8 Correct 2 ms 384 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 640 KB Output is correct
2 Correct 2 ms 640 KB Output is correct
3 Correct 2 ms 588 KB Output is correct
4 Correct 2 ms 512 KB Output is correct
5 Correct 2 ms 508 KB Output is correct
6 Correct 2 ms 640 KB Output is correct
7 Correct 2 ms 640 KB Output is correct
8 Correct 2 ms 384 KB Output is correct
9 Correct 2 ms 512 KB Output is correct
10 Correct 2 ms 512 KB Output is correct
11 Correct 2 ms 640 KB Output is correct
12 Correct 2 ms 384 KB Output is correct
13 Correct 0 ms 512 KB Output is correct
14 Correct 2 ms 512 KB Output is correct
15 Correct 2 ms 640 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 71 ms 22136 KB Output is correct
2 Correct 71 ms 22020 KB Output is correct
3 Correct 70 ms 22264 KB Output is correct
4 Correct 66 ms 20728 KB Output is correct
5 Correct 67 ms 22008 KB Output is correct
6 Correct 51 ms 20324 KB Output is correct
7 Correct 62 ms 21628 KB Output is correct
8 Correct 70 ms 22136 KB Output is correct
9 Correct 57 ms 20344 KB Output is correct
10 Correct 70 ms 22136 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 512 KB Output is correct
2 Correct 2 ms 384 KB Output is correct
3 Correct 2 ms 384 KB Output is correct
4 Correct 2 ms 384 KB Output is correct
5 Correct 2 ms 384 KB Output is correct
6 Correct 2 ms 384 KB Output is correct
7 Correct 22 ms 10872 KB Output is correct
8 Correct 2 ms 384 KB Output is correct
9 Correct 2 ms 640 KB Output is correct
10 Correct 2 ms 640 KB Output is correct
11 Correct 2 ms 588 KB Output is correct
12 Correct 2 ms 512 KB Output is correct
13 Correct 2 ms 508 KB Output is correct
14 Correct 2 ms 640 KB Output is correct
15 Correct 2 ms 640 KB Output is correct
16 Correct 2 ms 384 KB Output is correct
17 Correct 2 ms 512 KB Output is correct
18 Correct 2 ms 512 KB Output is correct
19 Correct 2 ms 640 KB Output is correct
20 Correct 2 ms 384 KB Output is correct
21 Correct 0 ms 512 KB Output is correct
22 Correct 2 ms 512 KB Output is correct
23 Correct 2 ms 640 KB Output is correct
24 Correct 71 ms 22136 KB Output is correct
25 Correct 71 ms 22020 KB Output is correct
26 Correct 70 ms 22264 KB Output is correct
27 Correct 66 ms 20728 KB Output is correct
28 Correct 67 ms 22008 KB Output is correct
29 Correct 51 ms 20324 KB Output is correct
30 Correct 62 ms 21628 KB Output is correct
31 Correct 70 ms 22136 KB Output is correct
32 Correct 57 ms 20344 KB Output is correct
33 Correct 70 ms 22136 KB Output is correct
34 Correct 64 ms 21496 KB Output is correct
35 Correct 50 ms 19448 KB Output is correct
36 Correct 57 ms 20600 KB Output is correct
37 Correct 3 ms 512 KB Output is correct
38 Correct 45 ms 19064 KB Output is correct
39 Correct 40 ms 18424 KB Output is correct
40 Correct 44 ms 19192 KB Output is correct
41 Correct 61 ms 21496 KB Output is correct
42 Correct 64 ms 21752 KB Output is correct
43 Correct 60 ms 20600 KB Output is correct
44 Correct 42 ms 18552 KB Output is correct
45 Correct 54 ms 20088 KB Output is correct
46 Correct 53 ms 19704 KB Output is correct
47 Correct 53 ms 19960 KB Output is correct
48 Correct 56 ms 20088 KB Output is correct
49 Correct 48 ms 18792 KB Output is correct
50 Correct 58 ms 20856 KB Output is correct
51 Correct 59 ms 20472 KB Output is correct
52 Correct 61 ms 21368 KB Output is correct
53 Correct 51 ms 20472 KB Output is correct
54 Correct 59 ms 21624 KB Output is correct
55 Correct 63 ms 21624 KB Output is correct
56 Correct 57 ms 21340 KB Output is correct
57 Correct 54 ms 20856 KB Output is correct
58 Correct 68 ms 21952 KB Output is correct