oj.uz

Submission #371462

# Submission time Handle Problem Language Result Execution time Memory
371462 2021-02-26T16:31:13 Z BartolM Boat (APIO16_boat) C++17
27 / 100
 2000 ms 28448 KB 
#include <bits/stdc++.h>

using namespace std;

#define X first
#define Y second
#define mp make_pair
#define pb push_back
typedef long long ll;
typedef pair <int, int> pii;
typedef pair <int, pii> pip;
typedef pair <pii, int> ppi;
typedef pair <ll, ll> pll;

const int INF=0x3f3f3f3f;
const int N=105;
const int MOD=1e9+7;

int n, m;
int A[N], B[N], povrh[2*N][N], siz[2*N];
pii p[2*N];
set <pii> S;
int dp[N][2*N][N][2];
#define DEBUG 0

int add(int a, int b) {
    a+=b;
    if (a>=MOD) a-=MOD;
    return a;
}

int mul(int a, int b) {
    return (ll)a*b%MOD;
}

int pot(int baza, int ex) {
    int ret=1;
    while (ex) {
        if (ex%2) ret=mul(ret, baza);
        baza=mul(baza, baza);
        ex/=2;
    }
    return ret;
}

int divv(int a, int b) {
    return mul(a, pot(b, MOD-2));
}

void prec() {
    for (int i=0; i<m; ++i) {
        povrh[i][0]=1;
        for (int j=1; j<=min(n, siz[i]); ++j) povrh[i][j]=divv(mul(povrh[i][j-1], siz[i]-j+1), j);
    }
}

int rek(int pos, int gr, int kol, int fl) {
    if (kol>siz[gr]) return 0;
    if (gr>=m) return 0;
    if (pos==n) return (!!kol)*povrh[gr][kol];

    int &ret=dp[pos][gr][kol][fl];
    if (ret!=-1) return ret;

    ret=0;
    ret=add(ret, mul(povrh[gr][kol], rek(pos, gr+1, 0, 0))); //nova grupa
    if (fl) ret=add(ret, rek(pos+1, gr, kol, 1)); //ne stavljam
    if (p[gr].X>=A[pos] && p[gr].Y<=B[pos]) ret=add(ret, rek(pos+1, gr, kol+1, 1));

    #if DEBUG
        printf("pos: %d, gr: %d, kol: %d, fl: %d ===== %d\n", pos, gr, kol, fl, ret);
    #endif //DEBUG

    return ret;
}

void solve() {
//    p[0]=mp(0, S.begin()->X-1);
    m=0;
    for (auto it=S.begin(); it!=S.end(); ++it) {
        if (it==S.begin()) continue;
        auto pr=it; pr--;
        p[m++]=mp(pr->X+pr->Y, it->X-!(it->Y));
    }
    for (int i=0; i<m; ++i) siz[i]=p[i].Y-p[i].X+1;

    #if DEBUG
        printf("m == %d\n", m);
        for (int i=0; i<m; ++i) printf("[%d, %d]\n", p[i].X, p[i].Y);
    #endif // DEBUG

    prec();

    memset(dp, -1, sizeof dp);
//    int sol=add(rek(0, 0, 0, 1), MOD-1);
    printf("%d\n", rek(0, 0, 0, 1));
}

void load() {
    scanf("%d", &n);
    for (int i=0; i<n; ++i) {
        scanf("%d %d", &A[i], &B[i]);
        S.insert(mp(A[i], 0));
        S.insert(mp(B[i], 1));
    }
}

int main() {
    load();
    solve();
    return 0;
}

Compilation message

boat.cpp: In function 'void load()':
boat.cpp:100:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  100 |     scanf("%d", &n);
      |     ~~~~~^~~~~~~~~~
boat.cpp:102:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  102 |         scanf("%d %d", &A[i], &B[i]);
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2075 ms 28448 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2075 ms 28448 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 31 ms 18540 KB Output is correct
2 Correct 27 ms 18540 KB Output is correct
3 Correct 30 ms 18540 KB Output is correct
4 Correct 30 ms 18668 KB Output is correct
5 Correct 31 ms 18540 KB Output is correct
6 Correct 36 ms 18540 KB Output is correct
7 Correct 37 ms 18540 KB Output is correct
8 Correct 37 ms 18540 KB Output is correct
9 Correct 36 ms 18560 KB Output is correct
10 Correct 37 ms 18796 KB Output is correct
11 Correct 33 ms 18540 KB Output is correct
12 Correct 30 ms 18668 KB Output is correct
13 Correct 35 ms 18668 KB Output is correct
14 Correct 32 ms 18540 KB Output is correct
15 Correct 32 ms 18540 KB Output is correct
16 Correct 20 ms 18540 KB Output is correct
17 Correct 19 ms 18540 KB Output is correct
18 Correct 21 ms 18540 KB Output is correct
19 Correct 21 ms 18540 KB Output is correct
20 Correct 20 ms 18540 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Execution timed out 2075 ms 28448 KB Time limit exceeded
2 Halted 0 ms 0 KB -