oj.uz

Submission #52965

# Submission time Handle Problem Language Result Execution time Memory
52965 2018-06-27T10:40:56 Z chpipis Boat (APIO16_boat) C++11
27 / 100
 47 ms 18132 KB 
#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define pf push_front
#define iter(v, i) for (__typeof__((v).begin()) i = (v).begin(); i != (v).end(); i++)
#define fast_io_without_cstdio ios_base::sync_with_stdio(false), cin.tie(NULL)
#define all(v) (v).begin(), (v).end()
#define rep(i, s, e) for (int i = s; i < e; i++)

// START for segment tree
#define params int p, int L, int R
#define housekeep int mid = (L + R) >> 1, left = p << 1, right = left | 1
// END

#ifdef __linux__
#define gc getchar_unlocked
#define pc putchar_unlocked
#else
#define gc getchar
#define pc putchar
#endif

#if __cplusplus <= 199711L
template<class BidirIt>
BidirIt prev(BidirIt it, typename iterator_traits<BidirIt>::difference_type n = 1) {
    advance(it, -n);
    return it;
}

template<class ForwardIt>
ForwardIt next(ForwardIt it, typename iterator_traits<ForwardIt>::difference_type n = 1) {
    advance(it, n);
    return it;
}
#endif

typedef long long ll;
typedef pair<int, int> ii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef long double ldouble;

const double EPS = 1e-9;
const double PI = 3.141592653589793238462;

template<typename T>
inline T sq(T a) { return a * a; }

//#ifdef LOCAL_MACHINE
//#endif

const int MAXN = 105;
const int MOD = 1e9 + 7;

inline int mul_mod(int a, int b) {
    return a * 1LL * b % MOD;
}

inline void add_mod(int &a, int b) {
    a += b;
    if (a >= MOD) a -= MOD;
}

int mpow(int a, int b) {
    int res = 1;
    while (b > 0) {
        if (b & 1)
            res = mul_mod(res, a);
        a = mul_mod(a, a);
        b >>= 1;
    }
    return res;
}

int a[MAXN], b[MAXN];
int s[2 * MAXN];
int nCr[2 * MAXN][MAXN];
int dp[MAXN][2 * MAXN][MAXN][2];

int main() {
    //freopen("", "r", stdin);
    //freopen("", "w", stdout);
    int n;
    scanf("%d", &n);
    vi pts = {0};
    for (int i = 1; i <= n; i++) {
        scanf("%d %d", &a[i], &b[i]);
        pts.pb(a[i]);
        pts.pb(b[i]);
    }
    sort(all(pts));
    pts.resize(unique(all(pts)) - pts.begin());
    int m = (int)pts.size() - 1;
    for (int j = 1; j <= m; j++)
        s[j] = pts[j] - pts[j - 1] - 1;
    for (int j = 0; j <= m; j++) {
        nCr[j][0] = 1;
        for (int k = 1; k <= n; k++) {
            if (k > s[j]) {
                nCr[j][k] = 0;
            } else {
                nCr[j][k] = mul_mod(
                    mul_mod(s[j] - k + 1, mpow(k, MOD - 2)),
                    nCr[j][k - 1]);
            }
        }
    }
    for (int j = 0; j <= m; j++)
        dp[0][j][0][0] = 1;
    for (int i = 1; i <= n; i++) {
        dp[i][0][0][0] = 1;
        for (int j = 1; j <= m + (i == n); j++) {
            for (int z = 0; z <= i; z++) {
                add_mod(dp[i][j][0][0], mul_mod(dp[i][j - 1][z][0], nCr[j - 1][z]));
                if (z > 0)
                    add_mod(dp[i][j][0][0], mul_mod(dp[i][j - 1][z][1], nCr[j - 1][z - 1]));
            }
            if (j == m + 1) continue;
            for (int k = 1; k <= i; k++) {
                for (int f = 0; f <= 1; f++) {
                    add_mod(dp[i][j][k][f], dp[i - 1][j][k][f]);
                    if (f == 1 && a[i] <= pts[j] && b[i] >= pts[j])
                        add_mod(dp[i][j][k][f], dp[i - 1][j][k - 1][0]);
                    else if (f == 0 && a[i] < pts[j] && b[i] >= pts[j])
                        add_mod(dp[i][j][k][f], dp[i - 1][j][k - 1][f]);
                }
            }
        }
    }
    printf("%d\n", (dp[n][m + 1][0][0] + MOD - 1) % MOD);
    return 0;
}

Compilation message

boat.cpp: In function 'int main()':
boat.cpp:89:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", &n);
     ~~~~~^~~~~~~~~~
boat.cpp:92:14: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
         scanf("%d %d", &a[i], &b[i]);
         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
0 / 9.0

# Verdict Execution time Memory Grader output
1 Runtime error 31 ms 632 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #2
0 / 22.0

# Verdict Execution time Memory Grader output
1 Runtime error 31 ms 632 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #3
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 42 ms 17620 KB Output is correct
2 Correct 41 ms 17696 KB Output is correct
3 Correct 41 ms 17808 KB Output is correct
4 Correct 39 ms 17908 KB Output is correct
5 Correct 45 ms 17908 KB Output is correct
6 Correct 37 ms 17952 KB Output is correct
7 Correct 37 ms 17952 KB Output is correct
8 Correct 39 ms 17956 KB Output is correct
9 Correct 38 ms 18132 KB Output is correct
10 Correct 38 ms 18132 KB Output is correct
11 Correct 38 ms 18132 KB Output is correct
12 Correct 43 ms 18132 KB Output is correct
13 Correct 37 ms 18132 KB Output is correct
14 Correct 36 ms 18132 KB Output is correct
15 Correct 47 ms 18132 KB Output is correct
16 Correct 18 ms 18132 KB Output is correct
17 Correct 19 ms 18132 KB Output is correct
18 Correct 18 ms 18132 KB Output is correct
19 Correct 21 ms 18132 KB Output is correct
20 Correct 18 ms 18132 KB Output is correct

Subtask #4
0 / 42.0

# Verdict Execution time Memory Grader output
1 Runtime error 31 ms 632 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -