oj.uz

Submission #111232

# Submission time Handle Problem Language Result Execution time Memory
111232 2019-05-14T10:59:16 Z tictaccat Boat (APIO16_boat) C++14
36 / 100
 2000 ms 1964 KB 
#include <bits/stdc++.h>

using namespace std;

#define int long long

const int MAX = 1000 + 5;
const int MOD = 1e9 + 7;
const int INV2 = 5e8 + 4;

int N,ans;
vector<int> a(MAX), b(MAX), ways(2*MAX), newWays(2*MAX), bin; //ways[i] = ways of ending between bin[i] and bin[i+1]-1
vector<vector<int>> Z(MAX);
vector<int> invs(MAX,-1);

int exp(int a, int e) {
    if (e == 0) return 1;
    if (e%2 == 1) return a * exp(a,e-1) % MOD;
    int temp = exp(a,e/2);
    return temp * temp % MOD;
}

int inv(int k) {
    if (invs[k] != -1) return invs[k];
    int D = 1;
    for (int i = 0; i < k; i++) {
        D *= i+1;
        D %= MOD;
    }
    return invs[k] = exp(D,MOD-2);
}

int choose(int n, int k) {
    int N = 1;
    for (int i = 0; i < k; i++) {
        N *= (n-i);
        N %= MOD;
    }
    return N * inv(k) % MOD;
}

int calc(int sz, vector<int> &z) {
    assert(z.size());
    int res = 0;
    for (int i = 1; i <= z.size(); i++) {
        res += choose(sz+i-1,i) * z[z.size()-i] % MOD;
        res %= MOD;
    }
    return res;
}

main() {

    cin >> N;

    for (int i = 0; i < N; i++) {
        cin >> a[i] >> b[i];
        b[i]++;
        bin.push_back(a[i]);
        bin.push_back(b[i]);
    }

    sort(bin.begin(),bin.end());
    bin.erase(unique(bin.begin(),bin.end()),bin.end());

    for (int i = 0; i < N; i++) {
        int pre = 1, k = 0; 
        for (; bin[k] < a[i]; k++) {pre += ways[k]; pre %= MOD;}
        for (; k+1 < bin.size() && bin[k+1] <= b[i]; k++) {
            int sz = bin[k+1] - bin[k];
            Z[k].push_back(pre);
            newWays[k] = calc(sz,Z[k]);
            pre += ways[k];
            pre %= MOD;
        }
        ways = newWays;
    }


    for (int k = 0; k < bin.size()-1; k++) {ans += ways[k]; ans %= MOD;}

    cout << (ans < 0 ? ans + MOD : ans) << "\n";

    return 0;
}

Compilation message

boat.cpp: In function 'long long int calc(long long int, std::vector<long long int>&)':
boat.cpp:45:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i = 1; i <= z.size(); i++) {
                     ~~^~~~~~~~~~~
boat.cpp: At global scope:
boat.cpp:52:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
boat.cpp: In function 'int main()':
boat.cpp:69:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (; k+1 < bin.size() && bin[k+1] <= b[i]; k++) {
                ~~~~^~~~~~~~~~~~
boat.cpp:80:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int k = 0; k < bin.size()-1; k++) {ans += ways[k]; ans %= MOD;}
                     ~~^~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 4 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 4 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 4 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 4 ms 384 KB Output is correct
16 Correct 3 ms 384 KB Output is correct
17 Correct 3 ms 384 KB Output is correct
18 Correct 3 ms 384 KB Output is correct
19 Correct 4 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 4 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 4 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 4 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 4 ms 384 KB Output is correct
16 Correct 3 ms 384 KB Output is correct
17 Correct 3 ms 384 KB Output is correct
18 Correct 3 ms 384 KB Output is correct
19 Correct 4 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct
21 Execution timed out 2043 ms 1964 KB Time limit exceeded
22 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 12 ms 512 KB Output is correct
2 Correct 8 ms 512 KB Output is correct
3 Correct 12 ms 512 KB Output is correct
4 Correct 12 ms 512 KB Output is correct
5 Correct 16 ms 540 KB Output is correct
6 Correct 47 ms 632 KB Output is correct
7 Correct 45 ms 512 KB Output is correct
8 Correct 45 ms 512 KB Output is correct
9 Correct 48 ms 512 KB Output is correct
10 Correct 46 ms 512 KB Output is correct
11 Correct 15 ms 512 KB Output is correct
12 Correct 9 ms 512 KB Output is correct
13 Correct 13 ms 512 KB Output is correct
14 Correct 12 ms 512 KB Output is correct
15 Correct 14 ms 512 KB Output is correct
16 Correct 12 ms 512 KB Output is correct
17 Correct 8 ms 512 KB Output is correct
18 Correct 8 ms 512 KB Output is correct
19 Correct 8 ms 512 KB Output is correct
20 Correct 11 ms 512 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 384 KB Output is correct
2 Correct 4 ms 384 KB Output is correct
3 Correct 4 ms 384 KB Output is correct
4 Correct 4 ms 384 KB Output is correct
5 Correct 4 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 4 ms 384 KB Output is correct
8 Correct 4 ms 384 KB Output is correct
9 Correct 4 ms 384 KB Output is correct
10 Correct 5 ms 384 KB Output is correct
11 Correct 4 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 4 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 4 ms 384 KB Output is correct
16 Correct 3 ms 384 KB Output is correct
17 Correct 3 ms 384 KB Output is correct
18 Correct 3 ms 384 KB Output is correct
19 Correct 4 ms 384 KB Output is correct
20 Correct 3 ms 384 KB Output is correct
21 Execution timed out 2043 ms 1964 KB Time limit exceeded
22 Halted 0 ms 0 KB -