Submission #41681

# Submission time Handle Problem Language Result Execution time Memory
41681 2018-02-20T12:33:14 Z gabrielsimoes Boat (APIO16_boat) C++14
100 / 100
182 ms 768 KB
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const ll MOD = 1000000007;
const int MAXN = 510;

inline ll mod(ll a) { return a %= MOD, a < 0 ? a + MOD : a; }

int n, va[MAXN], vb[MAXN];
vector<int> splits;

ll dp[MAXN], sum[MAXN];
ll inv[MAXN], bin[MAXN];
vector<ll> v;

int main() {
  inv[1] = 1;
  for (int i = 2; i < MAXN; i++) inv[i] = mod(-(MOD / i) * inv[MOD % i]);

  scanf("%d", &n);

  for (int i = 1; i <= n; i++) {
    scanf("%d %d", &va[i], &vb[i]);
    vb[i]++;
    splits.push_back(va[i]);
    splits.push_back(vb[i]);
  }

  sort(splits.begin(), splits.end());
  splits.resize(unique(splits.begin(), splits.end()) - splits.begin());

  for (int i = 1; i <= n; i++) {
    va[i] = (lower_bound(splits.begin(), splits.end(), va[i]) - splits.begin());
    vb[i] = (lower_bound(splits.begin(), splits.end(), vb[i]) - splits.begin());
  }

  for (int split = 1; split < splits.size(); split++) {
    ll len = splits[split] - splits[split - 1];

    sum[0] = 1;
    for (int i = 1; i <= n; i++) sum[i] = (sum[i - 1] + dp[i]) % MOD;
    v.clear();

    bin[0] = 1;
    for (int i = 1; i <= n; i++) {
      if (i <= len + i - 2)
        bin[i] = mod(mod((len + i - 2) * inv[i]) * bin[i - 1]);
      else
        bin[i] = 0;
    }

    for (int i = 1; i <= n; i++) {
      if (va[i] < split && vb[i] >= split) {
        v.push_back(sum[i - 1]);

        for (auto p = v.rbegin(); p != v.rend(); p++) {
          int cnt = (p - v.rbegin()) + 1;
          if (cnt == 1)
            dp[i] += mod((*p) * len);
          else
            dp[i] += mod((*p) * bin[cnt]);
        }

        dp[i] %= MOD;
      }
    }
  }

  ll ans = 0;
  for (int i = 1; i <= n; i++) ans += dp[i];
  printf("%lld\n", ans % MOD);
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:38:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int split = 1; split < splits.size(); split++) {
                             ^
boat.cpp:21:18: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
                  ^
boat.cpp:24:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d", &va[i], &vb[i]);
                                   ^
# Verdict Execution time Memory Grader output
1 Correct 9 ms 248 KB Output is correct
2 Correct 9 ms 352 KB Output is correct
3 Correct 9 ms 552 KB Output is correct
4 Correct 9 ms 552 KB Output is correct
5 Correct 9 ms 552 KB Output is correct
6 Correct 8 ms 580 KB Output is correct
7 Correct 7 ms 580 KB Output is correct
8 Correct 9 ms 584 KB Output is correct
9 Correct 8 ms 608 KB Output is correct
10 Correct 8 ms 608 KB Output is correct
11 Correct 8 ms 608 KB Output is correct
12 Correct 8 ms 620 KB Output is correct
13 Correct 8 ms 748 KB Output is correct
14 Correct 8 ms 748 KB Output is correct
15 Correct 7 ms 748 KB Output is correct
16 Correct 3 ms 748 KB Output is correct
17 Correct 3 ms 748 KB Output is correct
18 Correct 3 ms 748 KB Output is correct
19 Correct 3 ms 748 KB Output is correct
20 Correct 3 ms 748 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 9 ms 248 KB Output is correct
2 Correct 9 ms 352 KB Output is correct
3 Correct 9 ms 552 KB Output is correct
4 Correct 9 ms 552 KB Output is correct
5 Correct 9 ms 552 KB Output is correct
6 Correct 8 ms 580 KB Output is correct
7 Correct 7 ms 580 KB Output is correct
8 Correct 9 ms 584 KB Output is correct
9 Correct 8 ms 608 KB Output is correct
10 Correct 8 ms 608 KB Output is correct
11 Correct 8 ms 608 KB Output is correct
12 Correct 8 ms 620 KB Output is correct
13 Correct 8 ms 748 KB Output is correct
14 Correct 8 ms 748 KB Output is correct
15 Correct 7 ms 748 KB Output is correct
16 Correct 3 ms 748 KB Output is correct
17 Correct 3 ms 748 KB Output is correct
18 Correct 3 ms 748 KB Output is correct
19 Correct 3 ms 748 KB Output is correct
20 Correct 3 ms 748 KB Output is correct
21 Correct 79 ms 748 KB Output is correct
22 Correct 79 ms 748 KB Output is correct
23 Correct 67 ms 748 KB Output is correct
24 Correct 74 ms 748 KB Output is correct
25 Correct 72 ms 748 KB Output is correct
26 Correct 157 ms 748 KB Output is correct
27 Correct 155 ms 748 KB Output is correct
28 Correct 153 ms 748 KB Output is correct
29 Correct 152 ms 748 KB Output is correct
30 Correct 10 ms 748 KB Output is correct
31 Correct 10 ms 748 KB Output is correct
32 Correct 9 ms 748 KB Output is correct
33 Correct 10 ms 748 KB Output is correct
34 Correct 10 ms 748 KB Output is correct
35 Correct 9 ms 748 KB Output is correct
36 Correct 9 ms 748 KB Output is correct
37 Correct 9 ms 748 KB Output is correct
38 Correct 9 ms 748 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 3 ms 748 KB Output is correct
2 Correct 3 ms 748 KB Output is correct
3 Correct 3 ms 748 KB Output is correct
4 Correct 7 ms 748 KB Output is correct
5 Correct 3 ms 748 KB Output is correct
6 Correct 4 ms 748 KB Output is correct
7 Correct 3 ms 768 KB Output is correct
8 Correct 4 ms 768 KB Output is correct
9 Correct 3 ms 768 KB Output is correct
10 Correct 4 ms 768 KB Output is correct
11 Correct 3 ms 768 KB Output is correct
12 Correct 2 ms 768 KB Output is correct
13 Correct 4 ms 768 KB Output is correct
14 Correct 2 ms 768 KB Output is correct
15 Correct 3 ms 768 KB Output is correct
16 Correct 2 ms 768 KB Output is correct
17 Correct 2 ms 768 KB Output is correct
18 Correct 2 ms 768 KB Output is correct
19 Correct 2 ms 768 KB Output is correct
20 Correct 2 ms 768 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 9 ms 248 KB Output is correct
2 Correct 9 ms 352 KB Output is correct
3 Correct 9 ms 552 KB Output is correct
4 Correct 9 ms 552 KB Output is correct
5 Correct 9 ms 552 KB Output is correct
6 Correct 8 ms 580 KB Output is correct
7 Correct 7 ms 580 KB Output is correct
8 Correct 9 ms 584 KB Output is correct
9 Correct 8 ms 608 KB Output is correct
10 Correct 8 ms 608 KB Output is correct
11 Correct 8 ms 608 KB Output is correct
12 Correct 8 ms 620 KB Output is correct
13 Correct 8 ms 748 KB Output is correct
14 Correct 8 ms 748 KB Output is correct
15 Correct 7 ms 748 KB Output is correct
16 Correct 3 ms 748 KB Output is correct
17 Correct 3 ms 748 KB Output is correct
18 Correct 3 ms 748 KB Output is correct
19 Correct 3 ms 748 KB Output is correct
20 Correct 3 ms 748 KB Output is correct
21 Correct 79 ms 748 KB Output is correct
22 Correct 79 ms 748 KB Output is correct
23 Correct 67 ms 748 KB Output is correct
24 Correct 74 ms 748 KB Output is correct
25 Correct 72 ms 748 KB Output is correct
26 Correct 157 ms 748 KB Output is correct
27 Correct 155 ms 748 KB Output is correct
28 Correct 153 ms 748 KB Output is correct
29 Correct 152 ms 748 KB Output is correct
30 Correct 10 ms 748 KB Output is correct
31 Correct 10 ms 748 KB Output is correct
32 Correct 9 ms 748 KB Output is correct
33 Correct 10 ms 748 KB Output is correct
34 Correct 10 ms 748 KB Output is correct
35 Correct 9 ms 748 KB Output is correct
36 Correct 9 ms 748 KB Output is correct
37 Correct 9 ms 748 KB Output is correct
38 Correct 9 ms 748 KB Output is correct
39 Correct 3 ms 748 KB Output is correct
40 Correct 3 ms 748 KB Output is correct
41 Correct 3 ms 748 KB Output is correct
42 Correct 7 ms 748 KB Output is correct
43 Correct 3 ms 748 KB Output is correct
44 Correct 4 ms 748 KB Output is correct
45 Correct 3 ms 768 KB Output is correct
46 Correct 4 ms 768 KB Output is correct
47 Correct 3 ms 768 KB Output is correct
48 Correct 4 ms 768 KB Output is correct
49 Correct 3 ms 768 KB Output is correct
50 Correct 2 ms 768 KB Output is correct
51 Correct 4 ms 768 KB Output is correct
52 Correct 2 ms 768 KB Output is correct
53 Correct 3 ms 768 KB Output is correct
54 Correct 2 ms 768 KB Output is correct
55 Correct 2 ms 768 KB Output is correct
56 Correct 2 ms 768 KB Output is correct
57 Correct 2 ms 768 KB Output is correct
58 Correct 2 ms 768 KB Output is correct
59 Correct 104 ms 768 KB Output is correct
60 Correct 76 ms 768 KB Output is correct
61 Correct 77 ms 768 KB Output is correct
62 Correct 89 ms 768 KB Output is correct
63 Correct 79 ms 768 KB Output is correct
64 Correct 180 ms 768 KB Output is correct
65 Correct 182 ms 768 KB Output is correct
66 Correct 182 ms 768 KB Output is correct
67 Correct 182 ms 768 KB Output is correct
68 Correct 180 ms 768 KB Output is correct
69 Correct 96 ms 768 KB Output is correct
70 Correct 73 ms 768 KB Output is correct
71 Correct 74 ms 768 KB Output is correct
72 Correct 78 ms 768 KB Output is correct
73 Correct 77 ms 768 KB Output is correct
74 Correct 18 ms 768 KB Output is correct
75 Correct 17 ms 768 KB Output is correct
76 Correct 18 ms 768 KB Output is correct
77 Correct 18 ms 768 KB Output is correct
78 Correct 20 ms 768 KB Output is correct