oj.uz

Submission #111229

# Submission time Handle Problem Language Result Execution time Memory
111229 2019-05-14T10:55:57 Z tictaccat Boat (APIO16_boat) C++14
36 / 100
 2000 ms 1404 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);

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 a) {
    return exp(a,MOD-2);
}

int choose(int n, int k) {
    int N = 1, D = 1;
    for (int i = 0; i < k; i++) {
        N *= (n-i);
        N %= MOD;
        D *= i+1;
        D %= MOD;
    }
    return N * inv(D) % 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:40:23: 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:47:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main() {
      ^
boat.cpp: In function 'int main()':
boat.cpp:64:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for (; k+1 < bin.size() && bin[k+1] <= b[i]; k++) {
                ~~~~^~~~~~~~~~~~
boat.cpp:75:23: 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 5 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 5 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 5 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 4 ms 384 KB Output is correct
17 Correct 4 ms 384 KB Output is correct
18 Correct 4 ms 384 KB Output is correct
19 Correct 5 ms 384 KB Output is correct
20 Correct 5 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 5 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 5 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 5 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 4 ms 384 KB Output is correct
17 Correct 4 ms 384 KB Output is correct
18 Correct 4 ms 384 KB Output is correct
19 Correct 5 ms 384 KB Output is correct
20 Correct 5 ms 384 KB Output is correct
21 Execution timed out 2049 ms 1404 KB Time limit exceeded
22 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 56 ms 504 KB Output is correct
2 Correct 38 ms 504 KB Output is correct
3 Correct 52 ms 504 KB Output is correct
4 Correct 50 ms 512 KB Output is correct
5 Correct 61 ms 512 KB Output is correct
6 Correct 140 ms 612 KB Output is correct
7 Correct 137 ms 504 KB Output is correct
8 Correct 148 ms 632 KB Output is correct
9 Correct 148 ms 616 KB Output is correct
10 Correct 146 ms 692 KB Output is correct
11 Correct 61 ms 504 KB Output is correct
12 Correct 40 ms 512 KB Output is correct
13 Correct 52 ms 512 KB Output is correct
14 Correct 51 ms 512 KB Output is correct
15 Correct 60 ms 504 KB Output is correct
16 Correct 40 ms 636 KB Output is correct
17 Correct 34 ms 384 KB Output is correct
18 Correct 32 ms 384 KB Output is correct
19 Correct 31 ms 472 KB Output is correct
20 Correct 37 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 5 ms 384 KB Output is correct
6 Correct 4 ms 384 KB Output is correct
7 Correct 5 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 5 ms 384 KB Output is correct
12 Correct 4 ms 384 KB Output is correct
13 Correct 5 ms 384 KB Output is correct
14 Correct 5 ms 384 KB Output is correct
15 Correct 5 ms 384 KB Output is correct
16 Correct 4 ms 384 KB Output is correct
17 Correct 4 ms 384 KB Output is correct
18 Correct 4 ms 384 KB Output is correct
19 Correct 5 ms 384 KB Output is correct
20 Correct 5 ms 384 KB Output is correct
21 Execution timed out 2049 ms 1404 KB Time limit exceeded
22 Halted 0 ms 0 KB -